Speaker cable length with monoblock amps?

I was with Bob and Curl at CES a couple times. Among others things Bob had great ears. Plus I had some of his TG Audio 5 feet long speaker cables I traded him for, and they were fabulous. Thus, I'm inclined to believe the five foot story.

Why five feet, rather than, say, four or six? C'mon man, a little common sense is called for.

I had some of his TG Audio 5 feet long speaker cables I traded him for

Maybe he made those cables one morning after having a little too much fun with C and T the night before, or too little of his Ethiopian coffee he liked, and accidentally cut them a foot short since the TG Audio website lists speaker cables starting at 4 feet and continuing in 2-foot increments.
One of his way back posts indicates he believed his HSR speaker cables (which were a single 16 awg soft annealed solid-core silver conductor in teflon tubing) sound the same no matter the length;

"Have made some in 20' and 16' lengths, but was unable to get the wire in the hose, a compromise....There are several sets in the 12-14' range and can't tell the difference between these and a 6' set"

You were lucky to have met him.