nope not quite so simple....
on tonite's brand new episode, Dr. Marvin Monroe was indeed alive, and he was quoted as saying
"I was just under the weather for a little white"
I didnt catch on because I'm on the West Coast, and we don't get the Simpsons untill 8pm cali time. This thread was created before that....
So there is indeed a timeline flaw in the Simpsons..
/nerd voice at the next simpson's cartoon artist convention:
"In episode #3356 Dr. Marvin Monroe is clearly stated as having died.
In episode #4684 Dr. Marvin Monroe was alive.