This is more of a ruling point than a deckbuilding point, but... I'm fairly certain that you can't use
Sneaking to heal UNLESS you don't meet the "cancel skirmish" requirement. Once again, I'm not positive (and I can't find anything definitive in the comprehensive rulebook), but I think that when you have parenthetical things like that that change the effect of a card, you don't get to choose -- you do whichever one is possible. i.e., the parenthetical text will actually override the initial text, often against the player's will.
For example, an
Isengard Smith is capable of discarding Anduril, because it's a weapon (even though it's an artifact). However, if you can spot 5 companions, his text changes, and he now discards all POSSESSIONS, meaning Anduril would be beyond his reach. I'm fairly certain you don't have the option of saying, "Well, I'm just not going to spot the 5 companions," because his text says "(... if you CAN spot 5 companions)." Not "(... if you CHOOSE to spot 5 companions)."
I know this isn't by any means official, but
the Lord of the Rings Online game plays cards that way. In fact, if you play
Secret Sentinels and there's an Orc out, you HAVE to discard two conditions, even if one of them is your own.
But, once again, I couldn't find anything in the comprehensive rulebook about it. But if things DO go this way, then you'd only be able to heal Smeagol if he has less vitality than the minions he's skirmishing. If he had MORE vitality, it would trigger the "cancel skirmish" effect, which obviously doesn't work because he's the Ring-bearer.
Anyway... does anyone have an official ruling on this? I'll keep scouring the rulebook, but I don't have high hopes of finding anything conclusive. =P