I'll start this off:

When an athlete abruptly sits after hard play, blood circulation slows, preventing much needed oxygen transport, CO2 removal. Lactic acid builds up, causing muscle soreness. Hence, the need for a proper warm down, massage, hot tub, etc.

Otherwise, warming up again could take 12 minutes of lethargic play, possibly longer.

Older athletes can be affected even moreso. Remember Gary Payton chiding Doc in 2005 for sitting him too long before reinserting him late in games? Doc agreed: Yeah, as an older player himself, if he sat for more than a few minutes, he was finished physically.
Of course, worst would be for the athlete, especially older ones, to take a cold shower or enter an air conditioned locker room for a 30 minute half time break. All while the visiting team benefited while sweating it up in the visitor's locker room (at least that was how things were back in the old Garden).

So, is Byran Doo to blame for our home game record? Should Ed Lacerte set up half-time hot tubs in the locker room for the Big 3? How hot should Danny Ainge make it?