My thoughts on IHS and these conditions:

Quote Originally Posted by dspeyer View Post
You'd be able to if you had some reason to do so, but the spell by its very nature makes this extremely unlikely. Now, if someone dominated you on top of another domination, and then had you IHS the first one away, that'd work fine.

Much like dominate, the very nature of the effect makes it unlikely to be IHSed away, but technically possible.

ability damage/drain/penalties (but not burn)
Okay, I can see the argument here, since both ability damage and drain are conditions. Definitely yes on the penalties, though, because you can end whatever is causing them.

poison (having it in your veins such that you will need a second save in the near future)
Hmm, depends on if "poisoned" is a condition. It's certainly not listed under the condition summary on the SRD, but I could go either way on this one.

Yes. Paralysis is a condition, and thus a valid target for IHS.

As in the spell? Well, IHS can make that spell stop affecting you. For a round, anyways.

Checked? What is "checked"?

No, because you're incapable of taking any actions, including initiating IHS.

ambush feats
I'd say no, because they're not a spell or a condition. At the outside, I'd say maybe you're immune to them, but then you'd have to be aware of them in the first place, which, given the nature of the feats, seems unlikely.

balefull polymorph
If you retain your mental capacity, yes.

I'd say no on this one, personally, but I can see the argument for it.

effects of ambush feats
I think I need more information if this is somehow different than what I addressed above.

It has also been pointed out that IHS completely ignores how powerful the inflicter of the condition is. Shouldn't a 20th level wizard be able to bespell a 5th level warblade and make it stick?
That's kinda the point of IHS, though, isn't it? To make it so you have to fight them on different terms than Hold-Person-coup-de-gace-with-scythe? Now you might have to use Scorching Ray, or Finger of Death, or Fireball, or any number of other spells that don't just autowin (even though there's still plenty of those, like Flesh to Stone or Power Word: Kill).

So, I guess I can see a few things that would need to be clarified, but nothing that requires anything more than talking to your DM; and, no, I'm not committing an Oberoni Fallacy, I'm saying that the problem isn't big enough to require a rewrite of IHS.