Yeah that's exactly what I was going to say, Pierre. The correct way to A/B it against the Full Shred would be to back the amp's gain down a hair. I'm not saying it would all of a sudden be cutting as razor sharp as the Full Shred, but some of the difference in dynamics heard between the Alt8 and any other pickup in our line-up is somewhat colored by the output of the pickup, and how it hits the preamp.
In short, I wouldn't say it's a compressed pickup by any means. If you listen close, you'll even hear that hard picking does seem to have a hard hitting punch to it and pump the amp. You say that you "presume it can't be open" due to it's output, but that's all the magic of the wind, the wire, and the Alnico 8 magnet working together. It is extremely open for a high output pickup. In a weird way, it's actually a pretty "freeing" pickup. It's like "finally a pickup with the tone and dynamics of a medium output pickup, with the gain of a high output pickup."