Yes - from my understanding, it is pretty school-dependent. I think I "lucked out," in a way, in that my two MCAT scores were actually on a totally different scale since they had recently changed the scoring system. So there was actually no direct way they could be "averaged" or compared identically. I essentially (and foolishly - happy to talk about that mistake again if needed) got around the same percentile on both exams, which I'm sure did me 0 favors! In my interviews, only my second exam with the new MCAT was ever actually brought up, for whatever that is worth.
If I'd had two scores on the same scale, it might have been different. I do tend to think your second score is considered slightly "more," but the context of your first score will still be really important. If you improve a ton, schools where you interview will likely ask you about what you did the second time (this happened to many of my friends while interviewing) or at least make a comment about being impressed, etc, haha. If you don't improve at all, they may not comment, but yes, this is something that I was led to believe can potentially hurt your application rather than help.
