To be honest, I highly doubt that dude is retarded. Here is why:
They opened a brand new giant 24 hour fitness super sport right by my house...before that they had a tiny little 24 hour fitness that was built way back in the day(old school gym....very old school) and only the hardcore bodybuilders/juice heads would go in there. Everyone else would drive 10 miles up the road because this litle gym was considered too "ghetto" for them.
So they tore it down, and built this giant new one. My point of telling all that, is now instead of just seeing the usual faces I used to see everyday I now see TONS AND TONS of new people that dont know what the hell their doing. And they are always inventing new workouts.
The other day I saw a dude that got 20lbs dumbbells and started swinging both of his arms in giant circles as his shoulder workout...he did 5 sets. That is just 1 example I have seen so far out of many. But to be honest its funny to me lol