As I noted above, this question is geared more toward the hobbyists like me who probably have more time on their hands to deal with these minor things, since I don't have a ton of hives... The idea here is to add a shallow channel and a thin bead of silicone caulk around the top edge of my boxes, so the compression from above will seal out any minor gaps. I normally only have tiny gaps if any, since all my boxes have 3/4" box joints and I am very careful to keep them perfectly square, but over time they warp a little. If I could seal them like this, the bees won't have to propolize all the joints, and maybe I wouldn't need to tape any for winter either. Has anybody ever tried this? Thanks!