Long post alert. My
2 cents would be not to use the 15-22 in a tactical carbine-like course. NOTE: My comments are generic considering the many differing courses out there.
While the majority of the form, fit and function of the 15-22 are similar to an AR platform, the object of a basic course is to hone/refine or even learn the basics associated with your platform. The follow-on course (or 3rd day in some cases) is where you learn to fight with your rifle. If you used your AR for some courses of fire, and the 15-22 for others, you'd be intentionally introducing differences in your techniques that could really mess up your muscle memory and training. As one example, let's say you have an extended latch charging handle (like a BCM gunfighter) and you've transitioned your double-feed drill to using your left hand to rack the bolt to clear the jam. I'm certain the 15-22 would let you down in that drill just due to the design of the handle and it's durability. As such, you may have to mod your technique, which defeats the idea of taking the carbine course. Add in the stress introduced in a course, and you could then magnify any issue you may encounter.
What follows was part of a discussion on another forum and I tend to agree with some of the advice as applied to a rifle:
"Skills you can work on effectively with a .22 equivalent to your normal pistol:
* marksmanship
* strong- and weak-hand only shooting
* draw stroke
* reloads
* transitions
* judgmental shooting
* shooting on the move… With SOM, the line between good .22 training and bad .22 training is definitely easy to cross. But like transition drills, SOM training can benefit from a .22 in terms of learning how to move your feet and position your body for a stable shooting platform on the move.
Skills you should not practice with a .22lr handgun:
* recoil management
* sight tracking
* rapid multiple shots on a single target
I've tried to set up my 15-22 as close to my AR platform as possible so I can practice those skills, with the same kit, that re-enforce tactics, techniques and procedures I utilize. There are some TTPs that don't translate well so I don't focus on those in my training. BTW-I'm in NO way implying I'm high speed, I'd just like to be a less drag.

I'm also trying new equipment and new TTPs to refine my skills.