When I was in KY, I lived in an HOA so a permanent antenna was a no-no.
I would set up a random wire end-fed antenna (Packtenna Mini to be precise) running from my deck to the back yard fence. We lived on a hill, so the deck end was about 6-8' off the ground. The fence end was 3.5' up. The ground sloped in 2 directions under the wire. I figured it would never work.
I hooked the antenna up to my IC-7200 via a tuner, and to my surprise I was able to hear lots of signals. From Lexington KY I actually (inadvertently) broke into a net with the net control in Tallahassee FL, some 600 miles or so.
I just received a Chameleon MPAS (somewhat similar to a Buddipole) and am looking to try it as NVIS as well.
As for the mortar example, it's a poor analogy. A mortar is a single round that goes up, then down and can be affected by wind.
The value of the NVIS is that it is a cone of radio signals that roughly describes a circle on the ground hundreds of miles across. NVIS is best used to stay in contact locally or when the geography (hills, mountains, etc.) get in the way of direct or low angle signals.
Our military uses NVIS - whenever you see a military vehicle with an antenna arched forward and secured, that's usually not a tied-down vertical whip, it's an NVIS and it is used in that tied-down position.
