Yeah.I remember noticing that on Red Rescue Team.Squirtle's dialog was cute at first,but just plain unbearable later in that game.But it's a nice touch that it's not really cookie cutter for each pokemon.As for this game,it's been forever since I went through the story,so I'm not sure how noticable it is in this game.

I started doing just a tiny bit of research into this, as this topic got me interested and I was planning on restarting my game anyways. I think your partner's dialogue is influenced by their IQ group. For instance, Piplup and Cyndaquil both have very similar dialogue in dungeons, most noticeable that they share the phrase "This is it! No excuses!" while fighting bosses. Chikorita on the other hand says something completely different while challenging a boss. Thoughts?