[marcoarment]

  Could the high resolution just be a boost in the 5-10k treble?

 
A boost in upper treble is certainly how many headphones sound crisp, but it also gets harsh easily.
 
Among the cans I've tried, the 009 and HE-6 outclass everything else in true resolution, mostly from their incredible speed and transient response, I think, without needing the upper-treble spike and without bringing that harshness. The HD 800 is a great headphone, but I can't say this about it. (And in my opinion, the HE-6 manages the detail-without-harshness balance a bit better than the 009.)