I've crocheted with plastic shopping bags cut into loops and tied together into 1 long strip, and I've knit with cotton fabric cut into strips. I've never used anything as heavy as denium or leather strips, though. I knit a vest with the cotton strips and then sewed a matching skirt.
With the cotton, I cut it into 1/2" strips on the diagonal, keeping it as a continuous strip by not cutting thru the edge, but stopping 1/2" from the edge, then going back the other way. I only had scissors so that's what I used.
Not really sure what you mean by 'jeans lace' - but if you can cut it into strips, I don't see why you can't knit with it. The bulkier the fabric, the larger needle size you'd need. I can't help but visualize leather being too bulky, though.
Good luck with your project - let us know what you decide to do and how it turns out.