I think you're right George technically speaking, but there will still likely be considerable current (little RF) flows in the area, unlike around the end of a 1/2 wave radiator which also shows little RF flowing, but minimal currents. I think this might have some affect on the 5/8 wave pattern that offsets the advantage it is suppose to have.
IMO, whatever RF comes from the bottom 1/8 wavelength is minimized due to the out of phase cancellation affect in that area of the antenna. I also think the only advantage an end fed 5/8 wave has over an end fed 1/2 wave is this 1/8 wavelength increase in height for the current maxima, and that is not much of an advantage even regarding the angle.
I can't prove it, but this idea assumes that the excitation in the bottom area of the 5/8 wave radiator skews the pattern negatively, which might then allow these two to respond about the same in the real world over real Earth, and in some instances we may see the differences in conductivity of the real Earth ill-affect or benefit one then the other...in a particular real performance installation.
I make this conclusion base on my comparison work, where I continue to see the antennas I use...produce much the same signals at a variety of different stations within about a 60 mile range. I add that I only record RX signals and at times I do get TX reports...that may at times indicate more differences than the RX signal I record might show. Assuming antennas are reciprocal, I don't understand such result when I see it occur. So that factor has to be taken into account as a variable.
This is not a scientific analysis of events in a controlled setting.
