Can S video cables be used as digital coax cables?

I have some expensive, old Nordost Optix Video Super S cables that are worthless in the scheme of things today. I believe that a good coax cable must be shielded and be 75 ohms. These Nordost cables have 75 written on them & are shielded. I found a place that sells an S video female adapter to a male RCA. If I purchased two adapters, one for each end of the S video cable, would these adapters make my Nordost S video cable an RCA coax cable? I know that the cable would plug into the RCA coax input & output of my source & DAC, but would it sound terrible? I was just wondering if anyone has tried this before.
I doubt that would work well, unless your DAC has essentially perfect jitter rejection.

S-video cables conduct two separate high frequency signals (luminance + sync, and chrominance), and have two corresponding return conductors. Passive S-video to rca adapters typically just pass the chrominance information through a capacitor and then sum the two signals together.

That kind of arrangement is non-ideal even for its intended purpose of S-video to composite video conversion, and for a 75 ohm digital signal would essentially result in a mess in terms of impedance matching and waveform integrity.

-- Al