Yes, we can think that clock cables are more easily "predictable", as the clock is stabel signal. But as far as I know your Tektronix 7854 is a 400 MHz oscilloscope - it will show coarse mismatches, but some manufacturers claim that audible differences can show in the GHz zone.
An important detail concerning most quality digital cables is that they should not be bent with a very small curvature radius - it will severally affect the performance.