Two Revel m20s as center: good idea?

I have two Revel M20s, which I am thinking of using, combined, as a center channel in my home theater system. Will two be better than one, and, if so, how to place the two M20s. Both below monitor, both to side, one above/one below, etc...??
Two are almost always WORSE than one. The interaction of the radiation from two sources of the same signals results in an irregular dispersion pattern. That said, some have made a case for one above and one below but, ideally, only one is needed.

Thanks, Kal, for the input. I like the idea of one above and below, IF i can just figure out how to place the speaker above a plasma monitor 3 feet from the wall behind...

As for the interaction problem (phase cancelation(, couldn't the same problem arise during conventional stereo playback, when, as in centrally placed instruments, both speakers are getting the same signal, so as to produce a central image? Or, when any speaker possess more than one midrange or high frequency driver, as many do?
The problem is less of an issue with stereo since there are distance-related phase shifts from a real central voice/instrument when recorded in stereo. If mono-miked and split, then the problem occurs and is one of the causes of issues with vastly multimiked recordings. As for the problems with multidriver systems in the crossover regions, that is certainly relevant and is the reason why the vast majority of speaker systems are vertical arrays. This confines the the interference to the vertical plane. Thus, a vertical pair of centers is less pernicious than a horizontal pair.