Herbert wrote:
"Do you know how to explain this so normal people can understand?"

I `m not a Guru, but I`ll try.

First, there was adispute about delay in an antenna loading coil. That
provoked attempts to measure the delay. Then the argument turned to the
measurement methods.

The antenna signal travels from the transmitter through the coil and
through the stinger until it reaches the tip where it is forced to
reverse course by the open circuit. All the signal which has not been
radiated or lost in waste enroute starts its journey back toward the
transmitter. This reflected energy from the antenna tip is of no help in
determining delay through the loading coil but the ripples it makes,
when it adds and subtracts from the waveform of the forward energy,
makes measurements difficult. Frequently a directional coupler is used
to measure the energy moving in one direction, while ignoring the energy
moving in the opposite direction, to get a meaningful measurement. Cecil
proposed a resistor matching the impedance at the tip of the antenna to
avoid a reflection. This also eliminates the troublesome ambiguity.

Testing is convincing, perhaps, but not really necessary as the delay
through a coil has been understood and quantified at least since Ampere
who died in 1836.

The ARRL Handbook, mine is from 1976, explains inductance on page 25:
"Since the induced emf opposes the emf of the source, it tends to
prevent the current from rising rapidly when the circuit is closed."

Delay is a well known function of inductors. In early times they were
often called "retard coils".

Best regards, Richard Harrison, KB5WZI