Ahhhhhh...right, these are a fly tied by a chap called Ad Swier from Holland. Looks like they have copied, added a slightly different head and renamed.
I tied one of these at one of the Orvis tie demo things that Ben held a couple of winters back. Dead easy.
Maybe I should sell them on Ebay if they are getting $22 a fly!!!
As for attaching the rear hook, if I want a fully articulated fly with lots of wiggle, I whip a length of 30lb Amnesia (or Berkley Big Game Leader) along the top of the front hook and super glue it, pop the pre tied rear hook onto the Amnesia and create a loop about 10mm in size and run it back along the shank of the front hook. I then coat in super glue and whip back down and up to the eye again, and more super glue. If you slightly crimp the sections of Amnesia that you want to whip over, it grips even better.
I have also used small berkley snaps at the rear of the front hook (tied onto a loop) so that I can change the rear hook for different colours. I then tie the front hooks in Red, Yellow, Black Orange and white, then the same for the detachable rears. That way I can have, say a Red front with a white rear, then if the pike start to get finicky, I can change the rear for a black one, etc etc. Also helps when hooks get damaged as you can change them over.
Hope that makes sense and is of some use?
I do have a few other methods of extending the fly but its too difficult to explain in words. Maybe I should to a SBS for them?