I haven't ridden tubulars in 20 years but did since the early '70s. Settled in on using Tubasti for all my wheels except my good race wheels got Clement, Tubasti is a little different from Mastic or Clement becasue it does not set up hard but keeps some tack. I never stripped my rims. The longer they had been going and the more tire glues I'd done the more I trusted them. After a few I knew I could do a dry pull and mount a spare on the road and have a well glued tire by the end of the ride.
I am going back to tubulars as my current rims and tires wear out. Velox is still making Tubasti and a quick check shows a lot of current vendors. I would have no issues with riding tires on Tubasti'd rims for years or riding them after they've been sitting a long time. (Yes, I'd blow them up to around 80 psi and give them a good, hard sideways push.)
My brush-less glue application technique was pretty simple, Squeeze on a toothpaste bead between spoke holes (amount varied on thickness and condition of the old glue), take a folded small piece of stiff paper or thin cardboard, bend it with my middle finger to the shape of the rim, and go around the rim using it like a squeegee to spread the glue. Toss the paper. Fast and cheap.
Ben