Why exactly are you wasting our time with a trivial point? Of course there are things 3e can't do, mechanically, and that's engage in uniquely 4e mechanics.
And I think you are fundamentally misunderstanding BryonD's point that nothing in 3e prevents you from playing like you do in 4e. Note that the antecedent discussion is about abstract nature of hit points and BryonD, in his statement, is agreeing with Pentius's interpretation that you could treat hit points as completely abstract in 3e, just like you can in 4e. There's nothing inherent in 3e that prevents you from playing [with completely abstract hit points] like you do in 4e. BryonD's point is that the same can't be said going the other direction. There are things in 4e (healing surges) that do prevent you from playing 4e (with mixed abstract/substantive wounds) the way you can play 3e.
None of that has anything to do with some competitive narrating of mechanics that are in one game but not the other.
But, didn't I just prove that there are things in 3e that prevent me from playing 3e in the manner that 4e would be played? In 3e I cannot have the "heroic return". You agree with me that I can't do that. Thus, there are things in 3e which prevent me from playing 3e the way I would play 4e.
Now, which of those things are more important will certainly vary by different people. Fair enough. But BryonD's point was that there was nothing I could do in 4e that 3e won't also do, but the reverse isn't true.
That's what I've just proven to be false. Like you said, of course there are things that we can do in one edition that we can't in another.
I hope you don't think that's what "corner case" really means, because I've been finding your use of the term dubious in this thread. Is knocking a PC into negatives and seeing them healed partially back outside the normal parameters of operation in D&D? I don't think so.
I've been pretty clear on how I mean corner case. The only time that the "serious wound" issue will ever come up in play is if the following are true:
1. A character is knocked into the negatives and not killed.
2. There is no magical healing available.
3. The wound is described in specific terms which clearly define what the wound is.
So, yes, I do think it's a fairly rare corner case and I do think it's one that the DM is painting himself into the corner with. For one, most of the time it isn't going to come up because you have magical healing readily available. For another, any wound which is described in less specific terms, such as the Sir Billingsley example above where his wound is described as a face full of blood, can easily go either way.
Now, where I am really having an issue is that people's suspension of disbelief seems to be so selective. It's perfectly believable, apparently, that a "deep gash" to the arm could be entirely recovered from in a matter of days, without any actual mechanical effect to the character, but, somehow, you cannot receive a "deep gash to the arm" if you have healing surges.
This is where I can't really wrap my head around things. If you have no problems buying the idea that a potentially crippling wound can be hand waved away in a few days, why does having two separate hit point pools, suddenly tip you over? (BTW, I'm using the general you here, not you, Bill91, just to be clear)
To me it seems like people have no problems believing six impossible things before breakfast, but that seventh? Not a chance.