I am a heavy starcher also. I believe it helps not only with the sandwiching but the quilting. I keep folded ufo's over the twin bed in my sewing room usually on top of the backing I have prepared.I have been known to throw them over the dining room table to keep flat. (Before jigsaw puzzles took over in the shut down) I don't sandwich until I'm ready to quilt. But if I get delayed in quilting something, I can quickly iron the sandwich at the fold to smooth it out again.