Yeah there seems to me more "actual implementation" schools of thought than just those two theory approaches. Strictly speaking, with the Geddes, you are not level matching the subs, you are just filling in the room modes with the extra subs. And the lesser sub can be at a lower volume (did I read 3 or 6 db down???).
It seems in implementation a lot of members do go with a level matching. Something along the lines of equal subs equal distance from MLP. Get the levels right, get the delays/phase right, and get the crossover right so it integrates well. If the second sub is lesser, this is the second time I've heard the recommendation to get it placed nearfield so it can keep up with the stronger sub. In this case I'd assume it's trickier to get the levels, delays, and crossover smooth... but that's the fun stuff. My second sub has been pumping the bass for something like 11 years, I'm sure it would look forward to some limited duties rather than try to keep up with the Rythmik FV15HP in route.
All of my inputs on this topic thus far are purely from reading, my first experiences will begin this weekend. So please, folks with the experience chime in.