Multiple subs w/ different crossovers

after reading audio forums for the past month with some frequency, it seems as though smaller subs have a better performance at higher frequencies (~80hz).
A recent thread over at the Hsu site was comparing the LFM-1 (based on the STF-3) and the STF-2. The user noted the LFM-1 went deeper and louder, but didn't have the same kick at the higher frequencies as the STF-2. Now, this could just mean HSU is better, but the consensus seemed to be that the 10" woofer was superior to the 12" woofer for those frequencies ranges.

So, I was wondering if anyone had tried using a smaller sub, such as the LFM-2 or the STF-1 wired up to their mains, setting the speakers to small with a crossover of 40hz or 60hz, and then having a larger sub connected to the LFE. In essence, this would have the main sub doing the <60hz work. The small sub doing the 60hz to 80hz work, and the main speakers doing the 80hz+ work. Comments?

I’m not sure how you came to believe the LFM-1 or it's similar-sized kin won’t serve well above 60Hz approaching 80Hz, but IMHO, whatever sources of information led to such an idea are at best speculative and at worst, well, blowing smoke.

yes, I will admit it is speculative. I was wondering if anyone had actually experimented with it.