Missed some clarity in Tahm's kit

For his passive stacks, there's no given time as to when the stacks decay. Same on his E's passive health regain - it doesn't say when the grey health starts decaying after combat.

Additionally, Tahm's W appears to carry enemy champions for less time than enemy minons/monsters, which also isn't specified in the tooltips. Adding some clarity to these things would help with some more of his precision - how long you can keep an enemy champ out of a fight, how long you should wait before re-engaging for a trade, how long you have before you lose stacks on an enemy, all would be good information to have before I flash in only to find that I no longer have stacks on an enemy.