Apparently you have never ran into some that even my 1300 ft-lb Air Cat impact can't loosen. I know it sounds like it should but there is just movement of the blade assy to keep it from doing it. On those it is blocking the blade, using a 3/4" pull bar with a 5 ft extension, I row boat the fasteners off with both feet on the deck and both hands on the extension. Definitely want to be using 6 point impact sockets.
These are mostly on Scag and Gravely ZTRs.