Roy
The picture of the "ready bag" for the storm jib made me realize that what you were describing was a project that I spent some time on last spring. What I intended was to hoist the storm jib flying, as from your ready bag. I wanted to move the storm jib back, thinking it would better balance the reefed main, and installed backing and a pad eye on the fore deck a bit behind the main deck cleat. I had a mast fitting made up, complete with tangs for running backstays, and determined where it should be placed. Before I installed the fitting I hoisted a block to that location and secured it with some lines, and then tried to raise the storm jib flying. I was unable to control the sail. Headed into the wind, it was plastered against the shrouds and when I turned downwind the loose sheets and clew wanted to brain me. This was just a normal day, maybe 15 knots or less,probably less, I can't remember, but made me realize that in serious conditions this would very difficult. You might try it with one of your jibs, though if it's a hanked sail, watch they don't put an eye out.
There probably is a way to do it, perhaps hoisting in a sleeve, but it might be better if the luff is supported by a stay.
Craig V1519