The Tatar trade was next level moronic, there is no other way to spin that one.
Challenge accepted. (I fully agree with the rest of your post though)
The first Tartar trade was a brilliant move, that became next level moronic when they benched him and then traded him before training camp WITH MORE ASSETS for a player who - at best - gets +10 goals/year, and then gave that player an extra $2.2million dollars a year.
To elaborate, here were the big trade deadline moves last season:
Paul Stastny, UFA -> 1st, 4th + prospect
Evander Kane, UFA -> 1st (con) 4th (con) + prospect
Ryan Hartman (19 goals) + 5th -> 1st, 4th + prospect
Rick Nash, UFA (avg 19 goals in last 2 seasons) -> 1st, 7th + Spooner, Belesky and Lindgren
Derick Brassard -> 3 team trade where Pens gave up a 1st rounder solely because he was signed for 1 more year.
Grabner, UFA (25 goals) -> 2nd + Rykov
20 Goal scorer RENTAL players were fetching 1st rounders. Tartar was under contract for 3 years (at a reasonable $4.8m/yr). Bringing in a consistent 20+ goal scorer as a rental at the standard price of a 1st rounder, but then getting two full additional seasons out of him (or 1.8 seasons and then trading him at the deadline to get some assets back) while only giving up a 2nd and 3rd is brilliant. Even if you look at it from the reverse angle it seems like an even better move - trading a 3rd rounder for a 20+ goal scorer for the playoff run is way below what the rest of the league spent, and then paying TDL rates but getting entire seasons of production for the next 2 years is brilliant.
The trade even worked for Detroit because it sped up the rebuild and it was evident Tatar was not living up to his potential on the club. That's why I'll always defend that deal, it's a very rare win-win trade.
What is not brilliant is benching Tatar (especially when perron is still in the lineup) and then moving him before training camp the following season. Vegas had a high chemistry team so its not surprising that Tatar didn't fully mesh at first (but riding the bench was not going to change that). It's also apparent that Tatar being under term was key for Vegas since they had multiple veteran UFAs they expected might leave, so he was supposed to bring some stability to the roster. I was interested to see how a clean slate/full training camp would affect Tatar's role on the VGK, so when they traded him along with Suzuki and a 2nd rounder for Patches I was dumbfounded. When they immediately extended Patches for 4x$7m it confirmed everything bad every Caps fan ever said about McPhee. He doesn't give that extra year to Neal to keep him, but instead brings in a 'replacement' who has never been as impactful as Neal, pays him more and coughs up a 20 goal scorer he paid 3 high picks for plus a blue chip prospect and another high pick just for the right to pay him more. Astounding. Vegas is going to be in for some dark times once MAF retires.
EDIT: Oh and i forgot the best part, McPhee even retained $500,000 in Tatar's salary so they're paying him half a million dollars to score game winning goals against them.