I think they upped his encounter rate. I was running around in forests doing his sidequest and the friendly monsters sidequest simultaneously, and encountered him four times in a row with no random battles in between.

I don't mind him, he's another one of FFIX's nice touches. It's pretty much impossible to get a lot of the questions right without a guide, though, unless you're saving, finding him, restarting when you get it wrong, finding the answer, and then hoping to get that same question again. Far too much of a chore.