I have a tent with a silnet floor and my thermrest slipping and sliding around in the night is driving me nuts! I've tried using the rubbery self liner underneath and it seems to help somewhat, but I was thinking if I could attach velcro to the tent floor and to the bottom of my thermarest in each of the corner areas that it would be set for the night. You'd have to line up the velcro pathes perfectly for all 4 corner areas to attach. Has anyone tried anything like this?