When he plays it's a plus and when he doesn't the C's are still the top team in the league IMO. But, I think he has worn out his welcome in that locker room. Last season he fit right in, played his normal amount of games and missed the normal amount of KP games with nicks and bruises.
Last year in the playoffs the calf injury happens and then the crazy track and field injury happens. The team wins the chip and all is forgotten. The team knows that his recovery will be long and he'll be good to go hopefully at the halfway point. But he comes back early and everybody's happy. Now all they have to do is manage the back to backs.
Then, he twists his ankle on Christmas and now he has the flu

I always look at the money.
KP has played in 10 seasons (missed 1 season completely) for a total of 491 games out of about 750 games. He puts up very very good numbers in his career and plays a big role in a good Celtics defensive scheme. He is a huge plus for any team WHEN he plays. He was the 4th overall pick and will have made over 230mil after this contract ends next season.
AL has played in ALL 18 years that he's been in the league. The lockout year he TORE his left pec. Out of the approximate 1480 games during this 18 year career, AL has played in 1128 (which will increase because this year isn't over). He puts up very very good numbers in his career and plays a HUGE role wherever he plays. He is a MUST for this team to be successful IMO. AL was the 3rd overall pick and will have made over 285mil when this contract ends after this season.
IMO, NBA players are not exempt from pocket watching. I'm sure they have heard and seen all the stories about KP and his injuries from plenty of players in the league. You have that co-worker who gets paid just like you, meanwhile you work just as hard and eventually that starts to become an issue. KP's seems like a good guy, but if we're both getting paid generational wealth money or in AL's case a lot less money (this season)and he's doing things that most NBA players his age only wish they can do, people take notice.
I hope KP is able to play a few regular season games and hopefully the majority of the post-season, but after that I'd look to cut ties for not only tax purposes, but to stop the insanity of his injury prone career to continue in Boston.