I hope you are correct (that the Federal Gov't is not setting precedent over even those with living wills).
There is some federal act they are amending. I didn't get the name... did anyone else?
This type of legislation will not save Terri Schiavo's life nor will it pass Constitutional muster. First, there's the expost facto problem, only procedural laws and Clinton's tax increases can be retroactive. Thus, a federal law regarding living wills not help Terri.
Second, the Constitution gives Congress no authority to pass such a law.
You cannot consent to be murdered.
If removal of a feeding tube is murder, then there are hundreds of such murders every day, and a legislative solution to the Terri Schiavo case will MOST CERTAINLY void all so-called "living wills".