I was in a city centre pub recently and felt the need to intervene as the barman was making a hash of my pint with the beer engine (not the B&C, btw). I gave him a few pointers and he replied "I'm useless with the cask beer".
The thing is that once you understand what's going on, and what you can and can't do, it's very straight-forward. A teeny bit of staff training would cure the problem.