This is a silly semantic question, but, e.g., Lembas says:
"Discard Lembas to ready attached hero and heal 3 damage from it."
I think I won't be alone in saying that I've used it to heal 2, 1, or even 0 damage, just for the hero readying. But is this technically allowed? We cannot trigger card effects if we cannot pay the cost, like Emery's action with <3 cards in deck. Can we partially fulfill the results of an effect?
There's a relevant FAQ entry that refers to encounter cards discarding resources (you do what you can), but I was just curious if there was official word at some point for player cards,