Advertised as being made for musicians or some crap. Combine that with hype/tin eared headfi'ers and there you go.
Yep. That seems to be the most plausible explanation -- the marketing of Alessandro as being more studio/neutral creates expectations that get propagated through collective subjective impressions. Differences (if any) between Alessandro and Grado are subtle enough to concede to expectation bias.
With that said, the MS-1 always seemed less bright to me than the SR60 or SR225 as well, so go figure
I'll admit I'm susceptible to biases though.