I e-mailed the folks at the link JohnN provided for spectra cord. Asked them about knot-tying characteristics of the product as I've read (maybe on ETS even) that Spectra fishing line presents knot-tying challenges (slippery, somewhat stiff) -- although allowing that the 7/64-in. is thicker, braided, multi-strand and might behave differently. Their helpful reply:

You are correct, because this is multi-strand there is give in the cord when tying a knot. With single strand, the spectra is fairly inflexible, so getting the loop in a knot to close is a challenge. And yes, the spectra is slippery. I have used this spectra to tie down gear on my car and it holds well -- and sometimes the knots are difficult to untie. The spectra is not like other cord -- there is some tensile rigidity to it. Some people don't like this quality when trying to use -- they want to lay flat or other folding/compacting uses.

YMMV