I grew up making PB&B by mashing the banana and peanut butter together in a bowl, tuning the ratio to taste at that time, and then applying the mixture to the bread. I'm starting to think maybe this was not the usual way?

Never encountered that! Interesting approach.

As long as there is no mayo involved, we're good ;)

I also mash the banana with peanut butter, but instead of putting it on bread, I put it on steel cut oats. Then add a small amount of milk and mix. Finally, top with honey.