So I had my system asplode on me so I might be late to the party. For some time Mayhem mode was disabled on Normal difficulty, around the time DLC start option was added. Well it is now re-enabled and allows to quickly start DLC on normal with Mayhem mode without running those early Pandora missions. So far everything has been the exact same as TVHM in Mayhem. It also seems some aspects are shared between both playthroughs (my bounty kill gravestakes popped up immediately upon going to that spot). So we can keep our TVHM progress for Takedowns and have a use for normal difficulty runs. Hope this helps someone debating resetting TVHM missions.