As an expert on The Origin of the Stooges, I think i should weigh in here. The complete, proper sequence was:
Shemp : Curly : Shemp : Joe : Curly Joe
Shemp only appeared in 1930's "Soup to Nuts" with "Ted Healy's Stooges" before leaving the Stooges. He returned in 1947 when health problems caused Curly (Shemp & Moe's real-life little brother) to retire.
The anomalous reappearance of Shemp in the celluloid record at first appeared to contradict the theory, but most experts now believe Curly to have been a neutral mutation within a single phylo-stooge-etic branch.
You Curly Joeists never quit.
Curly Joe never happened! NEVER NEVER NEVER.
Prove 'Curly Joe' happened. You can't. All you have is old footage with him in it, which I will conceed is evidence for 'a theory of the Stooges really sucking bad' but not enough to convince me!
There was Shemp and Curly and it was good. There might have been a Joe (micro Stooges sucking) but there is no conclusive evidence of Curly Joe (macro sucking).
Nothing will convince me otherwise!!!!!! (see how many exclamation marks I use).