I definitely like having grown a strain/pheno a few times before.
But I've been so focused on my search, that I haven't had the room to run a group at once. Now that I've found a couple mainstays though, I'm starting to consider running 3 at a time. I have that extra tent ... 
I have an old ugly Carnival survivor that's functioning nicely as a mother right now, so I'll probably take a bunch of cuts and run the best of 'em. As you say, I'd like to focus on a strain I know and really see what I can do with it. 
Im curious about feeding 1 or 2 of the 3 plants that share the same soft pots, Cat since their buds are further along than the other one. I would do this by feeding it from the smaller tiers, on top. Would it greatly effect the non Cat drenched plant too?
It's the soil you're working on, and I would think most of the roots are in the shared pot. You'd still get the effect from the quart or so in the small pots. I bet the effect would work it's way throughout the larger pot. You might be able to manage a sort of timed release. 
