Riley,
I once did the same thing with Eucalyptus bark. We had a load of poles delivered for a project and they came bark on. I wound up with a huge pile of long bark strips that just begged for a cordage attempt. It worked but the bark seriously dried out my skin.
Bark is not the easiest material to learn on, it tends to be very irregular and stiff. If you really want to practice you need to have a good supply of material. I was fortunate in that I was able to buy both Buriti Palm and Sisal fibers in bulk cutting out the time consuming process of producing the fibers. I have processed the fibers of both from the raw plants, it is much easier to plunk down a few dollars for a 1 kilo sack of fiber and then work on points for style.
There are many ways to twist cordage. Every time I watch someone do the reverse wrap I feel pretty good about the way I make it, finger-twisting, for lack of a better term. Every time I watch someone experienced in thigh rolling I feel like a white man with a camera. I would love to see a twist-off between the various methods. I have no doubt thigh rolling will win hands down.
The bottom line is that you have to be satisfied with the cordage you make and at the rate you can produce it. With all of my materials prepared I can turn out about 15 feet in an hour with most materials and the quality works for me. Is that good enough? For traps, shelters, repairs, and fishing lines yes, for making a hammock or a net, no.
In cultures that make and use hand made cordage I have only seen thigh rolling and they crank it out at a rate that is impressive, gossip speeds the process. I know I have a long way to go. Down in Brazil I have a 100+ foot roll of high quality three ply cordage made by the Krikati Indians. This is clearly a skill that can be worked on. Mac
