OK, I am gonna get nitpicky. My beef with this short is that they are not real plumbers. They are mistaken for plumbers. So of course they know nothing about plumbing. To me, it would be funnier if they were portraying real plumbers.
Everyone remembers the plumbing scenes, but about 4 minutes go by before they pretend to be plumbers, and about 5 before they start a-plumbing. I am not saying, however, that the first 4 minutes are not funny.
Given its reputation, and the fact that it is over-shown, I am always a bit disappointed overall when I watch it. I consider it, however, to be a well above average Stooges short. It is not one that I reach for to view that often, however.