So, today I learned about gems ! Namely, that the "can't burn more gems than your path level" thing includes the gem consumed to go up the path. And no, that one upgrade gem doesn't let you burn a second gem.
Which in short, means : crap, crap, crap, I'm even more screwed than I was before, it's not even funny.
I also learned I suck at predicting my opponents, defending my territory and raiding. But I already sort of knew that
PS : Hope it stings, Niefel !