There's one reason hanging on the rim is a "T".
Not as dramatic as a Chocolate Thunder job but still scary for the guys on the floor.
THey call that a lot less than they should. Fans get pissy when it is called but I have long been a proponent of the whistle. If they are going to dunk ...FINE....if there is someone in the area ....fine.....there is no reason to grab the rim on a dunk. Slam it and move on....