In my humble opinion the button labeled 'Click to insert a dead hang bridle' is misnamed and causes confusion.
As a qualified & ticketed class1 rigger, I would opine that there is no such thing as a 'deadhang bridle' (happy to be corrected of course). In my world, a bridle has 2 or more 'legs'.
What this button should refer to is 'Click to insert a deadhang dropper'.
A 'Deadhang dropper' is usually used to extend the length of the hoist chain down from the rigging point if the hoist chain is too short for the height of the venue roof. It can also be used from the truss up to the hoist hook if the motor needs to be 'out of camera shot'.
A Dropper (or 'Stinger') is usually FSWR with a thimbled eye on either end.