I would think he'll get it and love it.
Good idea to 'put a word to what he's doing', then he'll get the idea.

Derek's technique for over-enthusiasm (in older dogs who should know better - you don't want to knock a youngster's enthusiasm, you may not get it back!) is to call the "That'll Do" - or in your case, whatever is your recall command - when the dog does his own thing, not what the handler 'suggests'. Clever dogs (which all BCs are!) soon learn that obeying the handler means staying on the sheep, disobeying means being taken off the sheep.
Of course, we don't know what sort of an 'eye' he has... nor quite how clever those Shetlands of yours are going to be...

and who learns faster !
Even if you only get him to run to the other side of the sheep and lie down and stay there, it'll be useful, huh?
If you can get 'Come Bye', 'Away', 'Lie down', 'Walk on' and 'That'll do', you'll be able to do most things.

Good luck - let us know how you get on!