It's still too difficult to conceptualise as an everyday, every-combat event. We talk about mothers lifting cars off of their babies because it's an exceptional event.I don't think any one aspect of hit points is particularly more realistic or less realistic than any other. They're a measurement of how hard it is to put someone out of this fight, nothing more, and that's at least as much to do with determination and morale as physical injury. Adrenaline does strange things to a body.
Healing surges and warlords make a formerly passable abstraction (hit points) which mapped to natural healing and magical healing, quite Ripley's Believe It Or Not because they've been abstracted further into the realms of the ridiculous by regaining them through being yelled at, schroedinger's damage, and other arbitrariness simply because they're a game design convenience.
In any case, I suspect the opinions in this thread are a waste of time. Mearls' post has the air of justifying or warming people up to the idea of something already decided, like the notorious "cloud gazing" blog entry preceding 4E. I find no sign in his words that much of what has driven people away from 4E is going to change.