I have had one hit the glass while rearranging his home.I don't think it was done for the purpose of breaking the glass.He didn't even crack it and he never hit it again.I don't think it is something they would try to do just to escape.I always felt like if one was trying to get out they were just exploring and not trying to run away.They are very curious little critters.But there are a whole lot of people on here that have much more experience with them than I do.They would probably know better than I would.
Yes, I was worried about my bimac crashing rocks around during den building prior to egg laying. She dug out the sand under a very large heavy piece of live rock and caused it to crash down. She was also lifting big pieces with the tips of her arms (she was strong!) and rearranging them. I saw this happening and ran and got my bag of shells. By offering shells for her building, I kept her from moving additional rocks.
So she didn't throw any, but she did topple the big one onto bare glass, which worried me.