That's a nifty little device you have there Carwi.......I may try one myself.

Doe Killer, be sure and get back to us with your results.

Seems to me that the 4 blade muzzy, even though the blades are only 1" deep, have more total area of blade, hence they should plan worse than the 3 blade. The way I see it is that 4 blades of 1" has more blade, more cutting surface than 3 blades of 1 3/16, by about 11%!
Althouhg this is not taking into account the length of the blades!