Tradeoff between Survical and APS

Yes, and that’s what separates a good energy management from ordinary ones. For where that point is, my experience told me that, it depends. For those don’t react on your bullet power (and firing relatively high power bullets), reducing bullet power earlier (e.g. immediately when having noticeable disadvantages) generally works, even for the extreme case iirc, e.g. reduce to 0.1 suddenly. I think that’s because the opponent is losing advantage shortly (for wasting energy), then you can fire normal power bullets again. (this increases both survival and bullet damage, some of the time). But for those reacting on your bullet power, this trick only cause them to keep their advantage, therefore making you lose the last chance to win.