The last quilt I sandwiched, I thought about using a rolling pin to press the glue into the fabrics and backing, but I didn't do it. I WALKED on it. It was on the floor, so I stepped to the left, brought my other foot up to that one and stepped again - across the quilt.
The cookie sheet would be used for that also. Pressing the fabrics together; a larger area at a a time. I don't think you can use it for smoothing.
I have a note book that I have been writing in since I started on this board. I have looked back and found things that I was looking for. What a mountain of information I get here; and sometimes I just go back and read my notes and find things that I had forgotten about.