I don't believe that characters necessarily win tournaments... I understand what you are meaning to say, but-
Pat is a new character (getting passed over by tradition). His strength (i.e. what would make players switch to him) is not immediately discernible like an Algol or Viola (you have to know his okizeme situations and when to 1K, otherwise he doesn't seem that great at first glance).
His range (and by association, his throw range) is terrible. He's not a flexible character, either you are fighting in the other guy's face or you are trying to set that up. He's strong, but you have to constantly play to his strengths, and I don't think tournament players want such specialization.
But I think the reason why you don't see him winning tournaments is because people just don't pick him (for whatever reason).
There's-
Kura (from Korea)
Something-Unique (sometimes)
KDZ (sometimes)
Partisan (sometimes)
ShenChan (sometimes - Singapore)
I'm having trouble coming up with names from that point. Only Kura I have seen play Pat 100%.
Really, try to look for tournament footage of Pat- There's not a lot. He's just not in it.
Pat cannot win majors if he doesn't show up.