I was surprised that they were using, well just pieces of plywood to tip the bundles out the door. When I did air-dispatching out of an Andover we kicked them out. It was my one and only episode at air-dispatching, offered to me as a one-off on Exercise Kangaroo-82. The plane was owned by the Kiwis but they hadn't brought any air-dispatchers with them and so we diggers got "volunteered". 
Later on TCTDF developed a semi-trackway for the Hastings which ran along the floor, and then turned outward by the rear doors. So then the dispatchers could shove the loads ALONG the floor rather than shove them OUT of the door.
Apparently they'd had a couple of occasions where the guys had gone out the door with the loads! They survived as they wore chutes during drops then, but I noticed that the guys in the vid had safety lines attached rather than chutes.