Sure but they'd be morons to sign a document with your wording in it.
The question here isn't "normal healthy people", the question here is how do we treat the weak, the young and the helpless.
My brand of conservatism says the primary purpose of government is to protect it's citizens and that extends to those citizens who can not fend for themselves. Those that will not fend for themselves but can do not fit into any of that category.
Yours is what?
I just looked up information on living wills at
http://www.alllaw.com/articles/wills_and_trusts/article7.asp
And it clearly states that a living will is only used when your ultimate recovery is hopeless, which was not the case here.
Sorry.