Something that bugs me about that scene is (and I know how daft it sounds) why is there a big open, barely fenced off bottomless pit in the room?

What is it for (other than chucking old bosses down when they threaten estranged family members)?

Would it be possible to cover it and have Vader chuck the floor plates around ESB style thus exposing the hole or maybe have the pit opened as a result of the damage caused by Vader cutting the footbridge?

These Sith love courting bad luck don't they?