While Bossy's 10-year career is pretty much consistently elite goal scoring, at similar rates and mainly in a similar scoring environment, Gretzky's are not.
There are at least four 'tiers' of Gretzky goal scoring:
1) 1981-82 to December 30, 1987 (Gretzky injured vs. Philly in his final Edmonton season)
NHL goals:
467 - Gretzky
343 - Kurri (75% of whose goals assisted by Gretzky)
335 - Goulet
332 - Bossy (didn't play 1987-88)
290 - Anderson
Gretzky scored 36% more goals than anybody else in the League. He led the NHL in goals in 1982, 1983, 1984, 1985, and 1987. He had 5-goal games spanning 1981 to 1987. He was 1 goal behind Mario when he got hurt in mid-season, 1987-88.
2) 1979-80 / 1980-81 and January 1988 to March 1994 (period ends the night be broke Howe's goals' record)
In his first two NHL seasons, he was around 4th or 5th best goal scorer, and in the latter period (mostly with L.A.) he varied (50 goals in 65 games his first season) but generally averaged around 40-45 goals per year, maybe ranking 15th or so overall.
3) 1995-96 to 1997-98
He's a productive but far from elite goal-scorer.
4) 1998-99
He can't score.
So, it's not like there's one Gretzky goal-scoring level to compare with Bossy. Whereas there is basically one, consistent Bossy level.
But I think Gretzky level (1) is well above Bossy's best level.
If you take their 9 best goal scoring seasons (1980-89), it's Getzky with
586 in
695 games, vs Bossy's
535 in
689 games (1977-86). You're including both of their prime runs. In this case, it doesn't look so bad.
I went with Gretzky's 1987-88 season (40 G/64 GP) over his 1979-80 season (51 G/79 GP), because while I think he's scoring goals at roughly the same pace (0.65 GPG vs 0.63 GPG), he's a significantly greater player in '88. Gretzky and Bossy look better relative to one other also, since Gretzky would be over 700 GP if I went with 1979-80 season instead. Either way...
Another thing to consider, is that there really weren't many 60 goal scorers in the East, over the duration of those 9 prime years that Bossy had played (1977-86). The only people to have done so would be:
- Guy Lafleur with 60 in 1977-78
- Mike Bossy with 69 in 1978-79
- Mike Bossy with 68 in 1981-81
- Mike Bossy with 64 in 1981-82
- Dennis Maruk with 60 in 1981-82
- Mike Bossy with 60 in 1982-83
- Mike Bossy with 61 in 1985-86
Also, how would Bossy's stats look if he reached 70 goals, twice in his career? Not to mention that he wasn't far off from 60 a few other times.
By comparison, 60 goals scorers in the West from 1980-89:
- Wayne Gretzky with 92 in 1981-82
- Wayne Gretzky with 71 in 1982-83
- Lanny McDonald with 66 in 1982-83
- Wayne Gretzky with 87 in 1983-84
- Wayne Gretzky with 73 in 1984-85
- Jari Kurri with 71 in 1984-85
- Jari Kurri with 68 in 1985-86
- Wayne Gretzky with 62 in 1986-87
- Bernie Nicholls with 70 in 1988-89
- Steve Yzerman with 65 in 1988-89
Of course, this looks great for Gretzky, because he's directly involved with not only his 5 seasons, but Kurri's and Nichols' seasons as well.
How about 55 goals (and up) in a season, starting with the East and Bossy from 1977-86:
- Mike Bossy with 69 in 1978-79
- Blaine Stoughton with 56 in 1979-80
- Danny Gare with 56 in 1979-80
- Mike Bossy with 68 in 1980-81
- Rick Kehoe with 55 in 1980-81
- Mike Bossy with 64 in 1981-82
- Dennis Maruk with 60 in 1981-82
- Mike Bossy with 60 in 1982-83
- Michel Goulet with 57 in 1982-83
- Michel Goulet with 56 in 1983-84
- Mike Bossy with 58 in 1984-85
- Michel Goulet with 55 in 1984-85
- Mike Bossy with 61 in 1985-86
- Tim Kerr with 58 in 1985-86
Now with Gretzky (1980-89) in the West:
- Marcel Dionne with 58 in 1980-81
- Charlie Simmer with 56 in 1980-81
- Wayne Gretzky with 55 in 1980-81
- Wayne Gretzky with 92 in 1981-82
- Dino Ciccarelli with 55 in 1981-82
- Wayne Gretzky with 71 in 1982-83
- Lanny McDonald with 66 in 1982-83
- Marcel Dionne with 57 in 1982-83
- Wayne Grezky with 87 in 1983-84
- Wayne Gretzky with 73 in 1984-85
- Jari Kurri with 71 in 1984-85
- John Ogrodnick with 55 in 1984-85
- Jari Kurri with 68 in 1985-86
- Wayne Gretzky with 62 in 1986-87
- Craig Simpson with 56 in 1987-88 (59 games, 42 goals with the Oilers)
- Jimmy Carson with 55 in 1987-88
- Bernie Nicholls with 70 in 1988-89
- Steve Yzerman with 65 in 1988-89
Okay, no real difference.
How about 50 goal scorers in the East (1977-86):
- Guy Lafleur with 60 in 1977-78
- Mike Bossy with 53 in 1977-78
- Mike Bossy with 69 in 1978-79
- Guy Lafleur with 52 in 1978-79
- Guy Chouinard with 50 in 1978-79
- Blaine Stoughton with 56 in 1979-80
- Danny Gare with 56 in 1979-80
- Mike Bossy with 51 in 1979-80
- Guy Lafleur with 50 in 1979-80
- Pierre Larouche with 50 in 1979-80
- Reggie Leach with 50 in 1979-80
- Mike Bossy with 68 in 1980-81
- Rick Kehoe with 55 in 1980-81
- Jacques Richard with 52 in 1980-81
- Dennis Maruk with 50 in 1980-81
- Mike Bossy with 64 in 1981-82
- Dennis Maruk with 60 in 1981-82
- Blaine Stoughton with 52 in 1981-82
- Rick Middleton with 51 in 1981-82
- Bryan Trottier with 50 in 1981-82
- Mike Bossy with 60 in 1982-83
- Michel Goulet with 57 in 1982-83
- Michel Goulet with 56 in 1983-84
- Tim Kerr with 54 in 1983-84
- Mike Bossy with 51 in 1983-84
- Mike Bullard with 51 in 1983-84
- Mike Bossy with 58 in 1984-85
- Michel Goulet with 55 in 1984-85
- Tim Kerr with 54 in 1984-85
- Bobby Carpenter with 53 in 1984-85
- Mike Gartner with 50 in 1984-85
- Mike Bossy with 61 in 1985-86
- Tim Kerr with 58 in 1985-86
- Michel Goulet with 53 in 1985-86
*Mike Bossy (bold) led the Wales Conference in goals 6 times in 9 seasons.
There were "35" 50 goal seasons throughout that stretch.
50 goal season in the West from 1980-89:
- Marcel Dionne with 58 in 1980-81
- Charlie Simmer with 56 in 1980-81
- Wayne Gretzky with 55 in 1980-81
- Wayne Babych with 54 in 1980-81
- Wayne Gretzky with 92 in 1981-82
- Dino Ciccarelli with 55 in 1981-82
- Rick Vaive with 54 in 1981-82
- Marcel Dionne with 50 in 1981-82
- Mark Messier with 50 in 1981-82
- Wayne Gretzky with 71 in 1982-83
- Lanny McDonald with 66 in 1982-83
- Marcel Dionne with 56 in 1982-83
- Al Secord with 54 in 1982-83
- Rick Vaive with 51 in 1982-83
- Wayne Gretzky with 87 in 1983-84
- Glenn Anderson with 54 in 1983-84
- Jari Kurri with 52 in 1983-84
- Rick Vaive with 52 in 1983-84
- Wayne Gretzky with 73 in 1984-85
- Jarri Kurri with 71 in 1984-85
- John Ogrodnick with 55 in 1984-85
- Dale Hawerchuk with 53 in 1984-85
- Jari Kurri with 68 in 1985-86
- Glenn Anderson with 54 in 1985-86
- Wayne Gretzky with 52 in 1985-86
- Wayne Gretzky with 62 in 1986-87
- Jari Kurri with 54 in 1986-87
- Dino Ciccarelli with 52 in 1986-87
- Craig Simpson with 56 in 1987-88
- Jimmy Carson with 55 in 1987-88
- Luc Robitaille with 53 in 1987-88
- Joe Nieuwendyk with 51 in 1987-88
- Hakan Loob with 50 in 1987-88
- Steve Yzerman with 50 in 1987-88
- Bernie Nicholls with 70 in 1988-89
- Steve Yzerman with 65 in 1988-89
- Wayne Gretzky with 54 in 1988-89
- Joe Mullen with 51 in 1988-89
- Joe Nieuwendyk with 51 in 1988-89
There were "39" 50 goal scorers during that stretch.
I was hoping to see that it's easier to score in the West in the '80s, but I don't see much evidence of that, at least not from looking at this.
Islanders
1977-78
GF: 334 (2nd of 18)
GA: 210 (3rd of 18)
3rd overall, 48/17/15 for 111 pts
Islanders
1978-79
GF: 358 (1st of 17)
GA: 214 (2nd of 17)
1st overall, 51/15/14 for 116 points
Islanders
1979-80
GF: 281 (12th of 21)
GA: 247 (4th of 21)
5th overall 39/28/13 for 91 points
Islanders
1980-81
GF: 355 (1st of 21)
GA: 260 (4th of 21)
1st overall 48/18/14 for 110 points
Oilers
1980-81
GF: 328 (6th of 21)
GA: 327 (15th of 21)
13th overall 29/35/16 for 74 points
Islanders
1981-82
GF: 385 (2nd of 21)
GA: 250 (2nd of 21)
1st overall 54/16/10 for 118 points
Oilers
1981-82
GF: 417 (1st of 21)
GA: 295 (7th of 21)
2nd overall 48/17/15 for 111 points
Islanders
1982-83
GF: 302 (15th of 21)
GA: 226 (1st of 21)
6th overall 42/26/12 for 96 points
Oilers
1982-83
GF: 424 (1st of 21)
GA: 315 (11th of 21)
3rd overall 47/21/12 for 106 points
Islanders
1983-84
GF: 357 (3rd of 21)
GA: 269 (4th of 21)
3rd overall 50/26/4 for 104 points
Oilers
1983-84
GF: 446 (1st of 21)
GA: 314 (10th of 21)
1st overall 57/18/5 for 119 points
Islanders
1984-85
GF: 345 (5th of 21)
GA: 312 (11th of 21)
9th overall 40/34/6 for 86 points
Oilers
1984-85
GF: 401 (1st of 21)
GA: 298 (8th of 21)
2nd overall 49/20/11 for 109 points
Islanders
1985-86
GF: 327 (8th of 21)
GA: 284 (5th of 21)
5th overall 39/29/12 for 90 points
Oilers
1985-86
GF: 426 (1st of 21)
GA: 310 (13th of 21)
1st overall 56/17/7 for 119 points
Oilers
1986-87
GF: 372 (1st of 21)
GA: 284 (10th of 21)
1st overall 50/24/6 for 106 points
Oilers
1987-88
GF: 363 (2nd of 21)
GA: 288 (8th of 21)
3rd overall 44/25/11 for 99 points
Kings
1988-89
GF: 376 (1st of 21)
GA: 335 (5th of 21)
4th overall 42/31/7 for 91 points
The Islanders were one of the best defensive teams throughout the time Bossy played for them. I don't think he was ever going to run up his goal totals, like he might have if he played on a different team. It wasn't necessary. The Islanders were winning cups by his 3rd year in the league.
If anything, looking through all of this, I've come away that Gretzky was always going to score more goals in the early part of the '80s, maybe more than anyone else could. And that's because he makes everyone around him better, and he yields the greatest returns as a result of this; extra space to work with (pick your poison, him or one of his teammates). His shooting style is also suited for that era (IMO).
Bossy's also at a disadvantage because:
a) he's not Gretzky, and he's not going to be able to create all of that extra space. He's depending more on his center to create for him. I think in a peak situation (with everything lined up perfectly), centers will have an edge over premier wingers for generating the absolute highest goal outputs.
b) it's really only his line, not that there wasn't any depth on the Islanders, but the Oilers have that next great line behind Gretzky (Messier and Anderson). The Kings lacked depth, but Bernie Nicholls was also great behind Gretzky (highest single season output over any of his more celebrated teammates). Gretzky's not only creating space within his own line, but for the 2nd line as well.
c) while he has Potvin (who I'm taking over Coffey any day of the week), Coffey is EXACTLY the guy you want on the point if you want to go from 160 points seasons to +200 points seasons. Gretzky and Lemieux had their greatest goal output with Coffey in tow. We could point to '92-'93 for Lemieux without Coffey, but I'd argue that the Pens two top lines specifically that season (in that high scoring environment) are greater than the best Oilers top two lines at any point, sort of making up the difference of not having Coffey.
I've often wondered if you swapped situations for Marcel Dionne with Gilbert Perreault, how much different their careers would have been statistically. I wonder the same of Gretzky. Would he have even had a single season of +200 points playing in the East (I'm skeptical that he would have done so)?
All of this doesn't matter though, because you can't separate Gretzky from his passing and his ability to get the most out of talent which surrounds him, which in turn, gave him more room (and opportunities) to score goals, over Mike Bossy.
I truly think that had he played with Gretzky, they both could have taken a run at 100 goals in a season. Gretzky recognizes how incredible of a goal scorer that Bossy was, he's said as much, so many times over the years. He admired how gifted Bossy was at it.