I never had any cutaways or locks pinned with less than the normal amount of pins - mostly I guess because I taught myself and did a lot of reading. I think it probably slowed my learning a little, but at the same time it made what I did learn stay with me...
I've only tried to teach one other person to pick locks, and that was very successful. He picked it up faster than I did, which I guess was to be expected, since he had my experience to learn from.
I think I started him out on some low security mortises and SFIC's (Corbin, Falcon, Yale, etc) , fully pinned (no security pins though). Once he was comfortable with that, I moved on to a Brinks lock with a few spools, then once he had that down, a Yale with 5 spools (6 pin lock).
After it was clear that he understood the principles and was able to pick low security locks consistently, we moved on to restrictive keyways and security pins. I think now, he's at the same level as I am - which means there isn't a whole lot left for me to teach him. I'm confident that if I can pick it, he can too. He picked it up a lot faster than I did, but I like to think that the knowledge I gave him was a factor in that. His pick making skills are not quite on par with mine - haha - but he can certainly make a usable pick.
I feel like I brought him up to speed very quickly, but now he's more or less on his own, as I am... I taught him everything I know, and now we're both stuck at the same plateau.
What took me a year to learn, I taught him in a few months. I'm not sure how much credit I can really take though - he just needed a little guidance to pick it up.
I guess what I'm saying is that I'm not sure if cylinders with only a few pins in them really help. Once they know what is happening inside the lock, I see no reason to use fewer pins than the lock would normally have in it.
But, like I said, that option wasn't available to me, so I don't really know how much it helps.