The shared cards on the table are 7,9,10,J,Q of Random suits with no flush possibility. One player has 8,8 and the other has 8,9. Is this a split pot since they both have a straight of 8-Q? Or does it make a difference that one player has the 8,9 in the hole?
This is indeed a split pot. Only the best five card hand each player can make matters at showdown, at least in Texas Hold 'em. The other two cards are irrelevant, whether they make an additional pair or extend the length of a straight. When the board makes something better than what you're holding, it's called getting counterfeited.