Judge Greer made the decsion about this case before it was heard, that is clear.
It may not be that he made the decision before it was heard (although there is a lot a speculation about ties, friendships, associates, etc). It is just that once he made two decisions (that Terri was PVS, and that she would want to die), he legally NEVER had to consider any evidence or question or dispute or affadavit or even miracle break-throughs that conflicted with the two facts that he had already decided.
That's where procedure trumps justice. The "facts" of the court NEVER have to be revisited. That is why he was able to throw out the claim of the DCF doctor. It disagreed with a legally found "fact" in the case, so he did not have to consider it at all. It had no place in his court.
Now, why he couldn't consider reason and common sense is another matter. What, overturn your own findings? Admit you, the infallible judge, is wrong? Does that cause one to question all your other rulings in all your other cases? Does the court system fall apart?
(Of course, this doesn't even begin to touch the alleged conflicts of interest and guardianship law violations. They are a different story....)