We are trying to train Gus to pee more reliably before bed.

Right now our tack is to take him out on the leash and give him a treat and big jubilation immediately upon performing a pee and then bring him straight back in. I am worried that this will result in teaching the behavior outside the yard, because we're taking him outside the yard to get the pee (he's a marker, so we don't have to wait long to get a pee). The thought is that once he associates the treat with peeing, we'll be able to offer the treat and get a pee IN the yard. Ultimately we want him to go out, pee and come straight back in when it's bedtime. We're using the command "go potty." It's not that he never pees in the yard, just not if he doesn't reeeeeeally have to (he does first thing in the morning).

Is our training logic messed up here? Other recommendations?