Davej wrote:So is there any clear logical division between
belay devices
and
descenders
?
Definitely, some belay devices work well as SRT descenders and some don't work well at all. Some descenders can be used as belay devices and others not so great. For instance I don't think a rack would make a very easy to use or efficient belay device. I've descended SRT on an ATC and it wasn't fun, I'd rather use a Munter than an ATC for SRT descent.
If you descend on a doubled rope with an ATC you can get a decent ride.
So I'd say there is a logical division but it has to be parsed through what techniques you like to use for tree climbing, based on that you can make decisions on what devices are going to be optimal for your climbing style.
-moss