This article by Dwayne McDuffie was published back in 2002, but I only just found it (which may explain why it's pointing to a site that's not yours).
Best. Quote. Evah! On the Tommy Westphall Universe:
All of these would help me prove my Grand Unification Theory, which posits: "The last five minutes of St. Elsewhere is the only television show, ever. Everything else is a daydream."
— Dwayne McDuffie, Six Degrees of St. Elsewhere
Still, if you really want the final authority on just how much television Tommy Westphall continues to destroy thanks to the final scenes of St. Elsewhere, you must check out crossoverman's fantastic page, Tommy Westphall's Mind — A Multiverse Explored.
This meta-filter entry is a good primer if you're still confused after reading the wikki entry on Tommy Westphall and crossoverman's web site
As you can tell, I'm a huge fan of crossoverman's work.