Is there a difference between the Social Points and the Trait Points? Because the Trait Points, like Trainer Insight, doesn't have the same bug, it only applies the point once, no matter how many times you go back and forth (I checked when I found this bug, just to be sure).
I'm not sure how the game's coded, so I'm unsure how significant the difference is between the two is that prevents using a similar coding to prevent the bug, so my apologies if I'm asking a dumb question.
Either way, the game's good thus far, so I can easily handle one or two bugs. Plus side, if additional dialogue for closer friends is added, at least there's a way to check them out without having to programme in a Friendship editor, eh?