Also living the pug life, and while I don't tank savage myself I bring a friend that does. It depends on the group comp and whether or not the DPS use their aggro management tools. When we pug savage, we have a group of 3 DPS and one tank - the rest of our party is made up of randoms. At the very least, the 3 of us who play DPS use our aggro management abilities frequently and we've never had a problem. Typically our random DPS is either not good enough to come close to taking aggro or they use their abilities as well.

If anything, we had one O1S group where our friend had to stay in grit the whole fight because the healers were terrible (and he still died to auto attack damage, even with grit on) but that's not the norm. With a NIN he can get away with one powerslash combo before dropping grit; without one, he does a few combos before dropping it. If your issue is with the OT, ask them to shirk you on cooldown if it's not needed for any swaps to help you maintain aggro.