Two pair wins the pot about 10%-12% in NLH. Given all cards get to the
river, the probability of holding two pair is 24%. In Four-Card Omaha (PLO),
two pair is rarely a winning hand, e.g., only 1-3% at showdown in full ring
game (6-9 players). As you can imagine, it’s even worse in Five-Card
Omaha (PLO).
