When everyone raves about how great Grado is at detail, I'm unable to shake the feeling that most headphones would sound like they have greater detail if you eliminated most of the bass because, well, you're able to hear the mids and treble more clearly since that's all there is. When the airwaves aren't pulsating with deep bass, you're much more able to hear finer points on instruments in the higher spectrum. I mean that's just how sound works.
It's no coincidence that the headphones everyone says have the best "clarity" and "detail" are the most treble-heavy. If you tilt headphones toward the bass, it'll sound muffled, like you have hearing loss. Tilt it toward the treble and it sounds sparkly. That might be why it's interpreted that way: hearing loss is typified by losses at the higher register. If you've ever been too close to an explosion or amplifier at a concert you know how the top end of the spectrum vanishes for a while until your ears recover. The "details" of a sound are all at the top. That's where you have the scrape of a finger on guitar strings, the pluck of the strings, scratches in a singing voice.
It might sound like I'm nitpicking, I just feel like it's worth saying that in the case of particularly the cheaper Grados they don't have great clarity, they're just treble monsters.