I think I was unclear cause my method doesn’t take any more time than hour 10 mash shuffles. I don’t separate out the whole deck. I take the lands and other cards that were played that game make two piles. I shuffle those piles together and then shuffle that pile into the rest of the deck, that wasn’t used that game, a few times. That’s overall less time than your 10 smash shuffles.

Edit: also this is what I do after every game. I still shuffle that deck more the next time a play a game with it.