The problem with that is that this metagame doubles a boost any ability gives. Thus, this is how it will stay. Honestly, if that was the case, I don't think this metagame would be fun, as people would be too confused to understand how to play it. Besides, what rule did you use to calculate that?
No, Parental Bond halves the base power of the attack the second time around. It doesn't work on stages. I don't exactly know for certain how the simulator works, but I'm assuming that it doesn't work on stages.