Well, I know of one rivalry/heated ego battle that's been going on for decades, and that's between Grady and Billy Incardona. In the accustats booth over the years they both love to say that the other ones opinion is wrong....And I've seen Grady get really steamed at Billy many times in years past when they gambled - Grady accusing Billy of sharking him etc.
Now I'm not in there heads, so I can't know for sure, ( and Grady, I apologise if you feel I'm speaking out of line ) but to me it always seemed like Grady truly, shall we say, disapproves of Billy, whereas Billy fights with Grady just because he enjoys aggravating him..........Any of you other long-time guys ponder this over the years ? - I'm sure fellow poolplayer-psychologist Freddy B. has.