Dan, N3OX, please no flames. That is not the correct style here ...

You are criticising by error, or by ignorance.
I did the measuring of the efficiency by feeding the RoomCap antenna with 1 KW HF,
havinga VSWR below 1,1 and the result: Less than 70 W heat is produced by the
antenna, and, as energy can not be destroyed, 930 W was radiated by the antenna.

The definition of efficiency by the IEEE is:
"The radiation efficiency of an antenna is the ratio of the total power radiated by
the antenna to the net power accepted by the antenna at its terminals."

You can measure these data your own, using your instruments in your laboratory.
The construction plan is available. You get it a a very moderate cost, for 30 Euros,
as contribuiton to the development costs.
This is less than you pay here in a restaurant for dining with a drink.
And you call that "business". Please keep realistic and study before
you accuse me of what you did.

Regarding the tests on 160m you commented:
I was testing between 22h and 24h local time, during the last weeks.
At this time no oversea stations were reachable due to the present conditions.
Even the biggest european stations were calling CQ DX, using Kilowatts, without
any reply from DX.
When calling on 1933 Khz, a pile-up of UK stations appeared. They all wanted to
contact me - and gave very good reports. Ask John, G3WWM and Eric, G3IMX
who are very familiar with the 160m band with decades of experience.

73s

Felix HB9ABX