*Slightly OT*

Can anyone give an opinion for why Coticules cut so much faster than Thuringers? If the grit is a similar hardness and the Thuringers are softer, they should allow more cutting media to be exposed. But in my experience, very few of either stone produce their own slurry (without a rubbing stone) which would imply that they are similar in hardness overall. So is it the shape of the grit particles or...?