I think the point of the experiment is how do you weigh the rights of people with life & death decisions.
My own view is that if you're in a hospital you are there to be helped and made better and obviously kept alive - this is irrespective of your wishes or those of your guardians. This assumes you have a prospect of meaningful life, as opposed to being in a permanent vegitative state (re terminally ill, see below), i.e. I think there are times to switch off the machine, again, sadly, irrespective of the wishes of the family (this may seem heartless, but in theory there could be wards full of people hooked up to machines with no prospect of recover but kept there by family praying for a miracle - recent incidents notwithstanding I think at some point you need to take heed of medical advice, perhaps you give a week or two for people to come to terms with it or to allow for the miracle but at some stage it makes sense to let go).
If you dont want treatment dont present for care (medical personnel have enough to be doing without wasting their time on nonsense like no blood transfusion), if you happen to be brought there by ambulance or whatever then you will be given appropriate care and discharged, what you do when you leave the hospital (in good health hopefully) is your own business, but dont expect to be let die by people who could save you.
While we're at it (sure lets get all medical dilemmas out there), I do believe that euthenasia (sp?) is morally acceptable - the key difference from the "no transfusions" brigade is that in this case you are terminally ill, you will die shortly without having recovered any quality of life, you have the mental capacity to make a decision, then fair enough, I dont see any benefit in being made suffer to the bitter end - you wouldnt let an animal suffer into death (ok you can pump someone full of drugs and arguably numb the pain but to what end?), I'd rather die without having weeks or months of twilight.