I agree that is someone isn't able to use a POW they shouldn't be the one performing the POW'ing task.
A scenario that I run across a lot when rigging down long limbs with one groundie is that it is way easier for the groundie to land them in a tight spot while not also trying to run the lowering rope, and not get the rope tangled in the brush at the same time. Then, they have to tie/ de-girth hitch the knotless sling, get the rope clear and restacked, and send the end up to me. The whole while, I sit there waiting. You can only pre-sling so many branches, then run out of things to do while the groundwork is being done.
When natural crotching or running through a pulley without a lowering device. I often will leave stubs near me for friction wraps so that I can cut while Ben catches the piece with the rope. I take control of the rope, and he lands the piece (we work around a lot of fragile landscaping).
As much as possible, I will both cut and catch the piece, leaving Ben free to land the piece and get the groundwork done.
This necessitates having stubs to later clean off, and having a suitable stub for a friction wrap, and only using a rope that handles abrasion well.
The difficulty comes most of all when we are lowering something heavy and using a POW. I can't hold the weight of the cut piece while getting friction wraps on a stub. Having an overhead lowering device seems like a great option. Bearing in mind that there is less rope in the system to absorb energy, and the inability to heavily pre tension the line might make this a good LD to couple with Polydyne rigging rope.
Two days ago, we were doing canopies raises on 2 doug-firs over a couple of sheds and a fence, with a narrow landing zone.
I shot an SRT line and ropewalked up to hang a pulley (conversely I could have used a Belay Spool, as well as shot another line to pull up a floating anchor for either pulley or BSpool). I worked off of both sides of the rope, one side using the spliced eye for a knotless system, and the other side an alpine butterfly midline (working midline line this has a built-in tagline for the groundie, which can be nice). While I cut rigged branches and lowered off stubs, Ben landed and disconnected, while I was getting set on the other side of the rope with the next branch. By the time he was clear of the DZ, I was ready to cut and lower the next.
I think that for this type of situation, the belay spool would be idea.
If you need more friction for some situations than other, one solution is to use an appropriately strong natural crotched floating anchor for the BSpool, lowering it down to the climber to be reset, then re hoisted and secured. If it is a thick barked tree or a removal, then adding a bit of trunk wrap friction can adjust for the additional load (using an appropriate rope). If there are a few bigger pieces to rig off, and the rest smaller, then a second friction device can be added at the base for those few heavier loads.
Perhaps this is a species specific type of situation.
I'll let you know what I come up with after I buy one. They are about $110 (apologies if I'm repeating myself).
Strange that on neither forum has anybody even mentioned bend radius.....
