You are right again.
No luck on silnylon, even with a flat finish, or even on PU coated nylon with a DWR finish opposite.
Seemed a tad on the heavy side, also. Will use VERY thin undiluted SilNet, as that is the most adhesive I've found (moreso than Permatex), and try to get away with rolling with a roller, but not clamping.
The roller was your suggestion also.
I think it will be a diamond stitch from my sewing machine manual on the seams I want to expand with the fabric, as that stitch worked well on lycra, so it ought to work on anything. Glad there was a thread on how not to get the needle gummed up; but if it does, well, then back to the tiny pins, and pulling them out as the fabric goes through the feeder.
Rome wasn't built in a day.