Brilliant!!!
The mind behind this guy is a comic genius!!!
Or....And I'm quiet serious here, he could have down's.
Seriously, this guy is either one of two things-
1. A wonderfully scripted comic ploy
2. A teenager with down's syndrome
I'm serious here...one of these options has to be the case. After carefully looking at the whole scenario, I really think that it could be option #2, which is why the joke hasn't gotten old to MW.
If this were a vet who was fucking around, the joke would have gotten old by now...as it has to most of us. MW keeps coming back. Hence my conclusion, that he is 16 year old down's patient.
I've always been taught that it's not polite to laugh at cripples, but in this case it's just too hard to resist.