Somebody already linked this article weeks ago. (And yes, this topic has been beaten to death on here.)
The article is basically nonsense. We need to understand the context of the times. In 1987-88, the hockey world was desperate for Gretzky to be dethroned, and his injury + Mario's great season finally gave them their chance. So, despite Gretzky's significantly higher rate of point production, and despite Gretzky's team doing far better than the Pens in the standings (the Oilers played .500 hockey when Gretzky was injured), the hockey writers could justify voting for Mario because he won the scoring title (only because of Wayne's injury). The Pens had a decent season, and were in contention for a playoff spot. On the last night of the season, probably after most Hart votes had been cast, the Pens lost in overtime and were eliminated from playoff contention (4 full years into his career, and Mario had yet to make the playoffs). Meanwhile, over in the Smythe, the L.A. Kings finished in 18th place (out of 21 teams).
Anyway, Mario got his Hart trophy.
A year later, and Mario and the Pens were again struggling (in the tough Patrick) to make the playoffs, despite super-Mario's most dominant season ever. They were only 5 points better in '89 than in '88, and while they did make the playoffs, they had to struggle down the stretch again. As late as March 24th (when they had 79 points with 5 games left), it appeared unlikely they'd make the playoffs. Meanwhile, after seven straight seasons of futility, the lowly Kings had improved to become the 4th-best team in the whole NHL.
So, that was the context as voters readied their pens in early spring 1989.
Here's how I view the Hart results vis-Ã -vis Gretzky/Lemieux:
1980 -- 1987: Gretzky won correctly
1988: Lemieux won, but I personally would have voted Gretzky. The Oilers had lost Coffey -- one of the most talented players in history -- and yet Wayne's point production per-game was actually slightly higher than the previous season. He clearly would have won the scoring title if not for injury, and the Oilers were on a 104-point-pace with Gretzky in the line-up. I would rate this season 60-40 in Gretzky's Hart favor, but with Mario playing the full season and voter-fatigue towards Gretzky, everyone (including Gretzky) knew Mario would win, and I don't really have a problem with it, except I don't like the Hart winner being on a non-playoff team.
1989: I personally would have voted for Lemieux, but I have no issue with Gretzky winning it. (Consider the context above.) I would rate this season 60-40 in Mario's favor, but I can (and could, at the time) certainly see the case for Gretzky.
1990: Neither Wayne nor Mario deserved to win (Wayne was great, but slumped along with his team after Nicholls was traded, and the Kings tanked in the standings; Mario missed far too many games and the Pens missed the playoffs for the 5th time in his 6 seasons).
1991: Gretzky was 2nd because of voter-fatigue + Hull's goal totals. While it is hard to argue with an 86-goal season, the fact remains that Hull was probably the 2nd-best offensive player on his team! Gretzky's Kings had their best-ever season and won the Smythe, and Gretzky had his best season in L.A. Not counting his own seasons, Gretzky beat every season in NHL history for scoring totals except two (Mario's 1988 and 1989). He won the scoring title by 32 points, and really should have won another Hart.
1993 and 1996: Lemieux deservedly won.