Basically yes, mainlining is great for closet/small area grows but takes some work.
The theory is that if you build a manifold all resulting colas will receive the same hormones/nutrients/etc as each other, resulting in a nice even canopy of fat colas.
When I'm back at a pc with my pics I will take some more so you can see what I mean by "manifold". The guy who started all this is over in the Subcool forum, names Nugbuckets... great grower, check his mainlining thread out, pics there that make it real easy to understand.
So far from other strains I have in flower that are semi-mainlined are doing great and as a technique it rocks, but, takes its time while you establish the manifold.
The BW I posted is in the process of being mainlined for 8 or 16 cola's depending if I can be bothered with the next set of topping before flower.