Odd length speaker cables

Sorry, Sonicbeauty, but you did relate these two variables in your statement and there is no scientific justification for it.

What works for me: I use a 16ft on one side, and 9ft on the other. This shifts the stereo image to the short side on the 9ft run.

I counter-balance this by advancing the 16ft side speaker about a foot in front, and the image centers beautifully.

Since you assert that you can fix the problem by moving the speaker a bit, you are extremely lucky or it is the result of something else.

The difference is not due to timing but in loudness. The longer cable is a bit weaker in loudness due to its higher resistance. Moving that speaker a bit closer to the listener makes it a bit stronger in loudness.

The difference in loudness is equally trivial and inaudible but I guess you can convince yourself of anything if you try.

BTW, I see there was a typo in my original post.  It should read:
" How can you possibly relate these? Moving the speaker 1foot
changes the arrival time (at the ear) by a bit less than
1millisecond. Changing the cable length by 7
------------------------------------FEET--------------------------------------------
changes the arrival time by about 0.0006microseconds."

The signal travels at close to the speed of light a few feet in difference of a cable doesn’t matter. The higher resistance of a few feet will not change the " loudness" it won’t change anything.

Of course.  :-)