[bliqpkxk] 8 to the bar

Hypothesize that in the phrase "eight to the bar", the "bar" is a dance bar of 8 beats, and not a musical bar of typically 4 beats.  (The 8 counts to a bar is why dancers count off 5 6 7 8 at the beginning while musicians count off 1 2 3 4, or "ah 1, ah 2, ah 1 2 3 4".)

If a dancer asks for 8 to the bar, e.g., "Beat me daddy, eight to the bar" (Andrews Sisters), then the dancer is asking for 8 strong beats to the dance bar, so a strong beat on every quarter note.  This contrasts to just 4 strong beats in a dance bar, a strong beat on every half note.  This distinction is the same as the "4 feel" and "2 feel" known to jazz drummers and rhythm sections.

A 4 feel is famously the style of swing music, with the bassist playing a note on every beat, often a walking bass line.  A 2 feel is famously the style of blues and rock 'n' roll.  (There are of course, many exceptions.)  A dancer asking for 8 to the means asking for a swing song as opposed to a blues or rock song.

This YouTube video, at 2'25", illustrates the difference between 2 feel and 4 feel.