In your early refresher marks, focus on steadiness, even going back to the belt cord if necessary to keep him from breaking.

He'll start creeping, even breaking. He'll start slipping whistles and refusing casts. He'll start switching and sucking back to old falls. Canine logic goes something like this: "If the boss' obedience commands are little more than tentative requests, why should I take his other, more advanced commands seriously?"

And yet so many people "hate to waste training time on basic obedience" after initially training their pups on these commands. But five to 10 minutes isn't much time out of a two- or three-hour training session, and spending that five or 10 minutes on a basic obedience refresher is not wasting time.

Actually, you can do most of it at home on your own, rather than while out working dogs with your training group. Just put in a few minutes early in the morning before work, a few more minutes late in the evening, just before bedtime.

You can easily keep your obedience refresher positive. Your dog knows the routine and any needed corrections can be quite gentle, like a jerk on the lead or checkcord. Thus, in each session you'll have abundant opportunities to praise your dog for good work. If you take advantage of these opportunities, both control and rapport will re-blossom.

Marking
Your retriever can get by as a hunting dog if he can do only single marks and blind retrieves. Granted, that's a minimum. It'll save you a lot of whistle-tooting and arm-waving if he also does multiple marks. However, with so little time to tune him up, you should concentrate on the minimum and then add refinements as time allows.

Give your under-worked and rusty M-M mostly single marks, especially at first. This will not only sharpen up his "marking eye," but will also build his self-confidence, as well as give you plenty of opportunities to praise him, thereby building rapport.

If you train with a more advanced group that does mostly multiple marks, let M-M do each mark as a single. Focus especially on keeping him steady. Don't let him break or even creep. You might go back to the belt-cord at first, so you can keep him steady without severe corrections.

After a few sessions, if he's doing quite well on single marks, you should add simple doubles, but only with preceding "rehearsals." First, run him on two singles and then on the pair as a double.

After several successful sessions this way, you might add an occasional very simple triple, with adequate "rehearsals." Run each of the two memory birds as a single, then those two as a double, and finally all three marks as a triple.

But keep everything very basic. You don't have time to challenge him with marks so long and hazard-filled that they might confuse him and undo the good you've accomplished.

Blind Retrieves
To keep everything simple in blind retrieves, you should give M-M mostly drills in the three parts of a blind retrieve, namely, lining, stopping, and casting. My book, Retriever Training Drills for Blind Retrieves, explains several drills for each of these three.

Lining drills encourage long, straight lines. Stopping drills encourage consistently rapid responses to the Sit-whistle. Casting drills encourage long, straight casts. Only when your dog is proficient in each of these three parts can he do a real blind retrieve properly.