For example, was the equipment (despite its apparently successful trial) deemed incapable of being integrated at reasonable cost?
Easy Street & DV
If you don't mind, I can answer.
The statement;
"The maturity of the design and technology allows design to proceed straight into prototype/C model production"
by definition means that the necessary Technology and System Integration Readiness Levels had been achieved, permitting the approving authority to sign for go ahead to launch production.
These two terms have changed a number of times over the years, but the meaning has remained constant; as directed by SofS based on advice from the Chief Scientific Advisor
.
Regulations say that the overall TRL or SIRL for an aircraft or system defaults to the lowest TRL or SIRL. So, for example, on Chinook Mk2 in 1993, while much of the Mk2 was at TRL/SIRL 6 or 7 (necessary to achieve, in today's money, Main Gate), the FADEC Safety Critical Software was at no more than Level 3 (i.e. grossly immature, in fact "positively dangerous"), so the entire Mk2 defaulted to 3. This is a fundamental rule of programme management. That is, no (legal) RTS could exist, as there was no proper authority to even begin conversion. Hence, Boscombe's refusal to fly/ grounding.
In stating this in his submission to OR(RAF), the Staff Officer is confirming the programme is at the necessary maturity level. No Staff Officer would make such a Submission without first having drafts approved, if only because he would not wish to place a Star rank in the position of rejecting something he had already approved. Such prior approval, in this case to conduct a TDP, would have had an aim - to achieve a certain TRL/SIRL, or determine what TRL/SIRL extant technology was at. Confirmation that this had been achieved would already have been sougth and provided - not least because payment would depend on it.
Hope this helps.