Yellowjacket, the area described above, is traditionally the most sandy section on the route. It can be bypassed via Highway 191. Both times I have ridden through YJ, however, the sand was not too bad.
The Entrada Bluffs section can get pretty shandy (Mike C's word), that is, a power-sucking combo of sand, shale, and loose dirt churned up from moto traffic. It's not a big deal if you are riding eastbound (from Moab), as this segment is mostly downhill. But climbing it (even during good conditions) is a challenge.
There is always potential for sand in Rabbit Valley (usually deep sand in short segments here, anyway), Fisher Valley, North Beaver Mesa, and all points in between, but traditionally the route is pretty solid. It's a beautiful ride - even the Cisco plains.
ditto--this sums it up quite nicely!
Curious if you are asking for a tire choice (if so-the answer is--due to the varying conditions all tire choices for the KT are a compromise)