Yes - good video - that's a good way to bend aluminum tube
Or, rather than bending around your stomach or knee, you can bend around a circular piece of plywood about two feet in diameter and then you don't need to fill tube with some substance to keep it from collapsing.
If you don't do it correctly, the tube will collapse.
With aluminum poles, if they're straight, and you put them on tent and bend them into that shape, they will probably collapse, but you could try it
polesforyou.com and http://www.questoutfitters.com/ sell Easton Poles that are 7075 aluminum, and come in either 18 or 26 inch lengths. You can buy either just tube, or a piece that as a slightly smaller diameter tube inside one end, that sticks out, so you can assemble several pieces into one longer piece when you set up tent.
look at quest website