It is just high time the devs did this. I would suggest a one minute timer before a player can drink another mana pot. I do not have any problem with failing more quests because quite frankly if I have to drink mana pots to beat a quest I do not deserve to beat the quest. Failing quests just makes the victories that much more sweet and encourages higher quality game play. There are no mana pots in D&D.
This game is too easy. 4 or 5 years ago DDO was so much more difficult. If you the devs are opposed to this on the normal or hard difficulties at least consider it for the elite difficulty. Thanks for striving to improve the game play.