Have you tried using dacron? I usually find that (I use rabbit hair) the rabbit strips get sawed apart before the connector does. I also use a really long shank for the first hook and tie my trailer a bit closer to prevent this. Hope it helps.
I posted an article on salmonfly.net describing the construction of a furled stinger for articulated flies. That method depicted in the article works equally as well with braided stainless wire as it does with mono and is probably a better material for toothy critters.
Another advantage is that with the furled stinger in place one can actually change the stinger hook, which is ompossible with a static tandem harness (one where the stinger is lashed to the connection and then glued or epoxied).
If you have any questions about the furling method, please feel free to contact me direct.
I find that wire affects the action too much. What would be the difference using wire versus a longer shanked hook? If you want the action, i think you need something flexible... I use our dacron halibut lines (80lb spectra) this is a similar diamerter to 15 lb mono. The action is uninhibited and the strenght is superb. If you are simply looking for a long leech pattern, i suppose wire would suffice, but i like the 'swimming' motion an articulated pattern provides.
Some of the braided stainless wires sold as leader material are vey thin in diameter for their respective breaking strength and are much more mobile than a single strand of wire. They also lend themselves well to the furling method mentioned in my earlier post. Another advantage is that when chewed on, the braided material is less likely to take a set or permanent bend.
I always use gel spun, like spectra, on my rediculated leeches. But, having caught pike before and having lost many because of their teeth, I would opt for some kind of wire even if it meant losing some of the action of the tail. Gel spun is amazing stuff, but surprisingly it doesn't take much of nick perpendicular to the line to reduce it's strength. Special knots are required just to tie it and even then, the knot can be reduced in strength by 50%.
Man I love Pike. They hit like a train. Way harder than Steelhead, but don't fight as well. Post some pics when you nail 'em
Powder monkey -
Try tying them without the second hook. Predators like pike usually take the bait/fly from the head so 1 hook is all that is really needed - tied a number of pike flies for friends and they report no drop off on hook ups with just one hook. A bonus is that the fly is easier to tie and fish.