One thing I did do with this warp that I don't usually do is.......... I have two threads in the last dent and the last heddle. Very seldom do I put two threads in the same heddle, but with this thread being so fine I thought it might help with breakage.
And - cross your fingers - I have not had a broken edge thread. I did have some when doing the sampling on this THREADING but not on this 12/2 rayon WARP. (I think that is what it is - label gone).