Cecil, W5DXP wrote:
"His virtual "center tap to ground" is certainly a valid concept."

Yes. Inertia is a valid idea. A balanced circuit remains balanced unless
something is done to unbalance it.

Work with phone lines and you find center-tapped lines are not required
for balance, or may make balance worse.

Equal exposure and occasional transposition usually maintain balance.

Best regards, Richard Harrison, KB5WZI