I have been experimenting with this technique and with ways to make it retrievable. The "weapon" is only cool if you dont have that stopper knot underneath it because how do you get the access line out when your done? SRT is the only real way but it can also suck to footlock up a single line.
By locking one end of the access line by tying a butterfly midline and pulling the tail through it to lock the rope off on the branch you can set a pulley on the locked off side of the rope but still have two lines to footlock up. This way you can still tye the marlinspike or whatever underneath the prussic. If the butterfly loop is big enough it will slide down over the pulley and knot. The ART block is good because it is aerodynamic and there is no caribiner involved. I spliced on a tenex eye and eye with one big eye onto the ART block to make the kleimheist easy.
the only downside is that you need a long rope. Another thing that I have tried is that when the rope isn't long enough to have the two lines touching ground with one side locked off, I will footlock up on one rope SRT until I reach the double rope. then before working I will set a prusic on the pulldown side of the access line with a hardware snap to catch the ART retreivle ball. This is snapped on right above my climbing hitch on the work line. Then when I am down, I pull on my rope and it goes through the pulley, catches the other line and I can pull down the whole system. Can you all visualize this? To do this though, you must decend in line with the access line which is not always possible. This is pretty much irrelevant because 200 ft of rope is plenty most of the time.
Another thing is that the pulley and the stopper knot (which I admit, I didn't even realize was called for before Nashville) must go through the crotch which can be a pain.
I have been using this technique for small jobs such as getting two limbs off off a roof or window and then coming down. It is great cause you can set your TIP up high and have all the movement but you dont have to switch over, set friction savers, and tie knots once up in the tree. Big time saver. I think though, that when climbing the full tree, there really is no point.