Biwire jumpers as speaker cables?

If they are long enough, yes. I have some 1 M Siltech F 12 ribbons that I have used both for mono blocks and jumpers. My 3" 14 gauge solid silver wire, not so much. Since I have seen everything from bell wire to welding cable used by someone somewhere as speaker cable there is no reason you couldn't do it. A good idea? Depends on the jumpers and your system configuration.

yes, that should work. Frankly, i am amazed you can get the jumper to reach...the terminals must be...what?...within 5 inches of each other? Super-close!

(BTW, I happen to have a pair of Transparent Audio Reference jumpers which I used with my SF Guarneris (since have sold the G's on)...but kept the Jumpers. If interested, feel free to email.)

Why not ? IMHO though I think 7 ft is about the minimum for any given cable to sound its best.