Over-healing should not generate extra threat

[Lemuria]

I could make you lose threat easily after 5 seconds into the fight if I wanted to with the crazy threat my 0 heals can cause believe you me

Unlikely, unless your tank sucks. Simple fact is that heals only generated half their restoration in enmity (so if you crit 3k, it's essentially the same as hitting for 1.5k damage), and tanks get aggro bonuses so that a simple 300 damage Halone combo is equivalent to 1500 damage, not including the bonus from Savage Blade.

As both a healer AND a tank, I don't really care much about generating 'extra' threat from overcures. Unless you're stupid, you'll never be able to generate so much as to be in any real danger. Usually the danger comes from new spawns joining the fray. Tank gets healed, so the mobs switch target because the tank hasn't generated any aggro.

Any tank worth their weight will be cancelling regen before dangerous pulls, even in speedruns, and any healer worth their weight will know when to cast and when to wait for the tank to get threat. Do we really need to start holding everyone's hands because they can't play their jobs properly?