Optima Cancel is part of the game as are the other tips. They are advance tactics that you pretty much need to use unless you want to make the game quite difficult.
Well that's interesting. Do you have a source that it's not a bug? Is it listed in a manual, in game tutorial, or developer interview? It seems like a very unusual and hard to figure out 'feature'. Why does it only activate when you switch back to optima config 1 and not some other config?
No, but I've not heard any thing about it being a bug except here. I also don't see how you could get 5 stars in a lot of battles without using it.