Agreed; with only the slightest access bees will chew up styro. When I first began using followers I just converted (blocked) the two outside frames, which was kind of a pain. I've also converted 10 frame supers to 8 frame simply by adding 1 inch styro with 1/8 Luann glued and facing toward inside. This works well but is/was permanent because I glued it in place, but bees cannot get to styro. There is NO access to the other side with this modification. I like movable followers for NUCs or small colonies slow to build up. I'm thinking I may experiment with styro in the middle and Luann on both sides which would allow follower to move and provide insulation and also allow for a more substantial top bar. Just some thoughts on follower boards, I love them and will continue to use them.