Oh, and here is a citation from the KN4LF web site that I have long
forgotten about conciously but my subconcious must have been nibbling
at because I suddenly had a compulsion to check his web site...
quote
************************************************** **********************************************8
Another note! When it comes to 160 meter vertical antenna's you can get
a lower take off angle (TOA) from a full 1/4 wave vertical or
electrical 1/4 wave tee vertical of 10-20 deg., versus ~30 deg. with
the inverted L. However it's a moot point as the night time E layer MUF
blocks 160 meter low angle transmitted radio signals from ever reaching
the F layer to be propagated. So unlike with HF propagation, MF
propagation success does not require the lowest of take off angles.
Also higher take off angles of 30-40 deg. via the inverted L are better
able to take advantage of the low signal loss E valley-F layer
propagation duct mechanism, a form of Chordal hop propagation.
************************************************** ********************************************
unquote

OK, so we are mixing theory with empirical results here, but, if having
the lowest possible angle of antenna response at 160 and 80 meters was
the best, by now a majority of the flagship contest stations would be
equipped with 5/8 wave vertical arrays, and they are not... I only know
of one major contest station that uses a 5/8 wave vertical on either of
the bottom HF bands...
My own experience is that the 1/4 wave vertical is superior on 160 but
not on 80... Nor is the half wave vertical on 80 superior to a high
dipole... The 80/160 vertical sits over a hundred half wave radials...
The high dipole hangs over forest with below average sandy soil......

denny / k8do