I'm not very happy about levering off the tower. It's one thing to use an unjointed tower structure to raise a deadweight, but quite another to apply massive side loads to it. These side loads are likely to be in the region of 7 tons at a height of 24 feet. I've said this before, but that's one hell of a torque. In order to counter that torque we would need some very long (70-100 foot) diagonal bracing poles against the tower, or guy ropes in the opposite direction, or both.

I'm also not sure that I agree about their lack of knowledge of gearing (I prefer the term "mechanical advantage" because gearing implies cogs and things). They already knew about using levers to attain a mechanical advantage. I could imagine that someone pulling on a rope might have thought to wrap it around a long branch, stick the end of the branch into a hole in the ground and then pull on the top to get extra leverage. An A-frame is not much more. In fact the job of an A-frame can be done with a single pole provided that tether ropes are attached on each side to stop it falling sideways.

I'm not arguing for one method over any other, but I think we shouldn't exclude any avenue of research that MAY end up being needed.