it says we are not worried that the cohen gadol would roll over his tefillin while sleeping. the tosfos in bava kama says that someone who has, for example a glass that's not his next to him on his bed and rolls over and knocks it down and it shaters in his sleep he's chayav. so why aren't we worried about the cohen gadol rolling over tefillin????????
moshe aryeh robinson, monsey,ny
Our Gemara is merely saying that we are not worried that this will happen. Tosfos is saying what the Halachah will be if it does happen, even though we might not have thought it would happen. Additionally, the monetary liability is not necessarily connected to the suspicion level that would determine whether or not we should forbid such behavior by the Kohen.
All the best,