i think it would work, and someone is selling it now for sticks using amsteel
i'm not sure amsteel would be the best as the hitch gets really tight
for NOT life support, which is what i consider a stick since i'm always attached while climbing via both lineman's and tether, i would consider two different size accessory cords, with a thinner one for the hitch...the extra friction on the sheath makes it work better i believe
i would feel okay with a 6 or 7 mm accessory cord for the main line and like a 5 or 6 mm for the prusik....but that's just me....the teeth of the stick digging into the tree with the rope camming it into the tree takes some of the weight
this will be quicker than the daisy chain trucker's hitch method, but not as tight....