Khabib said when he was not cutting weight as an active fighter he was near 190lbs. Khabib always struck me as a real solid 185lb dude when he's not dropping weight. Have you seen his cuts? Some of the most brutal I've seen, had organ failure from them, missed a couple times, his face would drastically change nearly Rumble like. If Khabib rehydrates 21lbs in 24 hours to 176lbs, it's quite obvious he walks around I the 180s. You said 30lbs, I'd say 5lbs tops, I struggle to see GSP even being 10lbs heavier. They're about the same size, seriously.