Attempting Double Sprang

All I can say is that this is not for the faint of heart.

This is my first trial at double-layered sprang.  It starts out with the black layer in ftont, and the lighter striped warp forming a layer in back, hidden by the black layer.

Keeping track of two layers was a new experience.  I tried using Peter Collingwood's method, and part of the way through switched to the method he describes as that used by E. Siewertsz van Reesema, which is to flip the work over and work the back row separately from the front.
Normally when working double sprang, you use these two layers, usually in contrasting colors, to form patterns of light vs. dark areas.  But I'm not really interested at this point in time in making patterns in flat fabric.  So I diverted from the normal method, and instead formed a slit in my front layer, and two slits in the back layer, so that I could bring a portion of the back warp through the slit to become part of the front layer.



This is the back side of the sample.  Part of the black front layer comes through the two slits to become part of the back layer.

At the top and bottom of the sample, see how the front and back are completely separate layers. 

They are also separate but different layers in the middle of the sample.  The layer on the left has a striped portion in the center, and the layer on the right has black in the center, where the two layers have changed places.

I'm hoping to use this interchange of layers in a sprang and woven piece, to have the portions of sprang twist around each other.  But I will have to figure out a method of working without flipping the piece over, since there will be a layer of weaving behind the sprang as well.

Thanks for reading!  How about you?  Have you worked in double sprang?  What was your experience?