hhmm? i have only used irish moss once, and the beer didn't seem any clearer than when i didn't use it. a lot of it has to do with transfer techniques, style brewed, yeast used, etc. i would say an all-grain will have potential for more suspended proteins in the final brew than an extract batch, due to the fact that your brewing from nothing but grains. an extract will yield a lighter SRM (color), and possibly be a little clearer than an AG batch. just my crooked way of thinking.....