proper practice is good practice.Any practice is good practice.
I like dry fire and one shot drills. I also shoot a bunch of 22lr.
That doesn't sound at all silly. It would be silly to think that one would be able to do these things under the stress of a real life situation without having practiced it until it was instinctual. Even better would be to drill with the other people in the household so everybody knows the plan to follow when something happens and can follow it without hesitation.I don't think that's a silly thing to do. Like you said, muscle memory is a very good thing and something you won't be able to buy to protect yourself/home/family like the gun you are practicing with.
Now this may sounds even more silly then just practicing the dry-firing/drawing. I practice from being in the bed to opening my safe to access the gun, and moving about with out making obvious noises, and aiming at spots where an intruder is likely to be at around about the house.
Just another way of building muscle memory my way, not every situation is going to be the same, but if you have a home defense gun, getting to know how you should go about using it to defend the house is not a bad idea.