J I'm sure if it can handle a fat lazy abseiler swinging around on it you should be okay hoisting tube on it.if I remember these things are also used for rescue situations,and I also no that no one has ever been killed through failure of abseiling gear..
there was an abseiller who died on the brents im sure he was using abseilling equipment that failed directly or indirectly.
if the BIG RIG was used something went wrong then when they come to in vestigate the incident they will ask for the paper work regarding the big rig the rope etc if you dont have it then you will be deemed to have acted negligently.
its a chance you take but rules are rules its up to you