My betting is that it was for a hip check. Our GSD has bad hip dysplasia and was put under to check what was going on. It wasn't a decision our vet took lightly either.
Some dogs naturally sit with their back legs like Henry, but it's also a classic sign of HD, and Cockers are a breed thats susceptible.
If that was the reason, then keeping his weight down is majorly important to help his joints! If our dog even teeters over 31kg, then the vet passes comment, which we completely agree with, so we keep a careful eye and exercise accordingly. PinochiSoph told everyone that the vet said he was an ideal weight though
Also, as a double coated dog why does she have him fully clipped? His fringe fine, but all over? Their double coats, kept natural, actually keep them cool in this hot weather, once clipped they find it harder to regulate their temperature. I'm speaking from a double coated breed owner too, so for once its nice to see him as he should be! Plus, it hides his rolls