I had an idea while reading Shadows of Self. Wax was given an anchor to test scaling buildings with by Ranette. My question is what would happen if Wax used a similar weighted line system, however instead of using the weight as an anchor to swing himself closer to something he uses it to pull himself through the air. The possible mechanics being that he increases his weight and then sends a quick shove on the weighted end of the line in an upward trajectory. He then stops pushing on the weight and decreases his own weight which would allow the weight on the line to have enough force to give him lift. Once his momentum tapers from that, he increases his weight, shoves the line again and continues the process.
You would probably have to do this very quickly and so it would take a lot of practice and I am not sure how economic it would be ferruchemically. Also I am not sure how accurately you would be able to fly.
Anyway, I am just trying to get feedback on the idea. Does it sound plausible?
As a side note, is it possible to steelpush or ironpull on a shardblade or shardplate? I am fairly certain that my memory is correct in that they are made of a kind of metal, though stormlight abilities are disrupted by them, would allomancy be as well, would they be like aluminum?