For enemies that deal consistant damage regeneration is VERY useful. For some enemies, you get hit infrequently or over time by a number of enemies. In that situation you want to use a normal healing poultice or the like, because you just want some extra health for later. But if you're surrounded and you know you'll be taking more damage in the forseeable future, you scarf a veggie cake so you have a cushion and you don't instantly lose all that life you just regained.
