In reply to David Coley:
Sounds like you came up with a good system in the end (though you will lose efficiency because without hauling using the rope, the stretch in the rope will mean some of your haul distance is lost when you relax the prussic cord to slide it down again.
I've hauled a few times with a 3:1 using the rope over an edge. Once it ripped my rope to shreds and every time it has been a complete ball ache. I've never hauled a heavy climber (max about 70-75kg).
If I had a reverso set up in guide mode and had to haul my partner a long way up, I would be very tempted to abseil down the dead rope to my partner and then use a combination of shoving them up by the arse (with my weight obviously pulling them up) and then prussicing up a little.
This has several advantages:
1) You get to the casualty quickly and can start to administer some sort of first aid.
2) You can take out all the gear on the rope which is causing drag.
3) With the gear removed, you can actually get the casualty to the ledge by hauling (without going down yourself the casualty is going to get stuck at the first bit of gear when you start hauling).
4) You can safeguard the casualty on the way up (check they don't get their head stuck under an overhang while you are hauling, etc.).