I think it's more likely that though I'd be initially aware of it at the point of magical reincarnation, by the time I reached whatever age it was, I wouldn't believe it was true anyway, so would act exactly the same as when I didn't know :)

Did that already in my first time around, with my highschool crush, when we were in college together. A premature "I love you" bomb. 2nd chance, if getting to that same point, I'd have heeded that little voice in me warning "don't say it, not yet, you'll ruin it". Or at the very least, not wimp out after, and instead continue to pursue her.