When I talked to the folks at Theta, they claimed that their goal was to reproduce the low end accurately, so that a string bass sound like a string bass, and an electric bass sounds like an electric. They claimed that certain amps with a lot of low end (not naming any names here!) tended to make everything so low end present that it started to make upright bass start to sound like an electric bass. Being a bass player (upright, acoustic, and electric), this was important to me. I have Thiel CS3.6's, and the folks at Thiel stated that they have had very good results with Theta amps driving their speakers, and they felt that their low end reproduction was excellent.
Nevertheless, it is always interesting to hear someone with a different perspective, especially a group of folks such as where Durbin directed us. Thanks for sharing that with us! However, I do feel that perhaps my personal listening preferences don't match up entirely with that particular test group.