I started a MLB league with the Yankees, basically going full tank mode. I'm also in commish mode to play around with Leadership and Morale. I started off trading a lot of guys, both at the start of the season after some time. E.G., I traded Andrew Miller (who has good leadership) to the Cubs for Javier Baez (lazy) and Ryan Kalish (shithead). Team starts complaining immediately, we actually started off 1-12 or some shit. They're constantly messaging me to do something to fix it, so I tried calling up different guys. Some guys with good intangibles helped bring up the mood a tad, others (Mason Williams, shithead) didn't help. So I bumped Didi's Leadership to 200 (he fills this role in real life tbh, I don't know why he was so low) in an attempt to fix it. I also bumped A-Rod, but I only saw an improvement when I did it to Didi, because A-Rod has max greed which apparently cancels out any good will.
Eventually Starlin Castro(shithead) and Masahiro Tanaka (just a normal guy) complain that the team is the tank and they want to be traded. Two other guys complain that the clubhouse is still kinda shitty. I traded Chapman for Gallo but didn't call Gallo up just to see if some of the other minors guys would help. I end up calling up C Hagioshka from AAA, who has the TAGGFECTA of VH LEAD/WE/INT. I also called up Slade Heathcott (shithead but he means well) and dumped Kalish. Team started doing okay, but we started bouncing back in wins. Think we got to like 16-22, which is pretty awesome with our bad start. But I wasn't sure if the bump was just rubberbanding, due to winning, or if it was because of the morale change. So I traded A-Rod to the Nats for Giolito, because yolo I'm in commish mode. Team starts doing awful again. We start tanking again and McCann asks to be traded. Anyways, rinse and repeat this over the year. Finished with 66 wins or something, BUCCOS won the World Series, edged out the Cubs in the NLCS because lulz.
But if you looked at the stats on my team, everything was off. Pineda, Nova, Severino, and Eovaldi all had ERAs over 6. Tanaka was at 5 and a half. Starlin Castro (who was petulant and wanted a trade from mid-April) had a Wrc+ of 82. More importantly, the guys I traded away saw huge bumps. Gardner went from hitting 82 WrC+ around June to over 100 the rest of the season in KC. A-Rod put up 2.5 WAR in half a season in Washington (who DID have a good lockerroom). McCann was hitting at 29 WrC+ until August and hit over 100 after a move to Cincinnati (who finished in a bad spot too, never checked their team morale).
I realized the power of Morale around August, so I decided to run another experiment. The White Sox were 8 games out of the wild card in early August, but they had a pretty good record (like 4 games over .500 or something). So I just went in and bumped the morale of some of their main players (Sale, Quintana, Frazier, etc.). They ended up tying the Jays for the last spot. Lost the play-in game, but yeah.
I'm still not sure how much is influenced by having shitheads/not having a "Captain" (this seems to only be guys with very high ratings in the TAGGFECTA; Guys with just 200 Leadership but average or worse WE/INT don't count. There's titles in the editor you can see in commish mode) and how much was by tanking. But my team definitely complained about both, and their performances showed for it.
Now granted this means tanking will be even easier because your team will play worse, but if you're trying to break out of tanking it seems impossible without a 'Captain' type player. I'll also note that player rating doesn't matter, I signed Nick Swisher and he naturally comes with Very High LEAD so he helped my team in that regard.