TBH I dunno what stuff is available in the NA version but Revolsio / Revolucio series was never good. If you're at the point where these are the only sheets available I guess it still makes sense, though.

Iirc these kinds of potentials work in increments, i.e. every 150k damage you deal your damage boost rises 1% so to hit the 6% you have to deal 900k damage first, and likewise 1% pp cost reduction for every 250pp used so you gotta use 900 PP to have a 6% reduction, etc.

I tend to stay the hell away from this kind of potential because it's very unreliable since every run is different which means sometimes it's easy to raise the counter and sometimes it's not.

BUT in this case I'd go with it because launcher is not that great for hitting weakspots due to the slow speed and fairly large aoe so the other potential of 6% weakpoint damage buff won't proc that much either.
Well, of course that is only if Delicate undertaking increases all damage and not just damage when hitting a weakspot.