Why did the clarity pots had immediate effects?
IF your mana pool is not at 100% you can use clarity potion, that is why i needed Unbeatable to burn my mana pool after resurrection.
IF your HP is not at 100% you can use Healing salve but they require "target" so you need to add mouse click and that makes healing slower and more complicated.
All potions and all items with "manually usable effect" trigger Iron Skin special effect and only Clarity potion and Healing salve have zeros seconds CD. Best items for this effect are Ice Shield and Ignite Scepter, both with about 5 seconds CD.