I imagine that the difference in elasticity between wool and linnen could cause problems, especially if the warp threads are unevenly spaced. How do you deal with that?
You are totally right, it does take quite the experienced weaver to do the warping and get the correct tention in both wool and linnen. In this weave we warp one linnen thread with one wool. When warping the linnen threads are made a bit longer to make up for the wools elasticity.