G'day peter,
You were quite right re the 20%. Found it in some saved files (I'm a real fan of the aircraft).
With respect to the "turbo ramjet", it was interesting to see in your Bob Abernethy link where he says,
Bypass the bleed air around the compressor at high Mach number into the afterburner and it would solve the surge problem, provide cool air to afterburner and increase the mass flow and thrust significantly. Actually it converted the engine into a partial ramjet with capability above Mach 3.
As to who may have been first to use the term "turbo ramjet" is moot I feel, as that is was what it was, as Bob alludes to.