Several years ago I was involved in recovering of a 1:1 Taylorcraft BC-12D. I did a lot of research on the stits system. The one constant through all of his videos and paperwork was that YOU DO NOT USE DOPE on stits type fabrics. Traditional coverings soak up and bond with the dope and cause shrinkage. The polyester based fabrics are shrunk with heat, and the plastic nature of the threads does not allow the dope to stick. It may fill the weave for a while while it's wet but when it finally cures out, it flakes off.

Have a look

http://www.polyfiber.com/stits/

http://www.stits.com/

HTH

Tom