Several issues here. In no particular order:
The first rotary wing tp course was run in 1963 - No1 RW
It ran alongside No 22 Fixed Wing and shared some groundschool lectures.
Before the first RW course all pilots destined to test helicopters did the FW course and were then given a helicopter checkout by a QHI at ETPS and learned their helicopter testing techniques on the job with existing helicopter tp guys.
I did No22 FW course but after being posted to AeroFlight because they had helicopters used for model dropping and other helicopter tasks (as opposed to helicopter testing) I was given a helicopter check out by the ETPS QHI.
Because of this when I flew the P1127 and SC1 later on I needed no prior helicopter famil.
To my knowledge nobody was ever checked out in the SC1 or any of the Harrier family without a few hours in a chopper to LEARN THE VISUAL CUES OF THE HOVER. (Not to turn them into chopper pilots). This may have changed when the RAF got 2-seater Harriers - I can't remember.
The Bedstead which was conceived and specified by the RAE for research and R-R got the contract to make it. After the R-R CTP Capt R T Shepherd RN showed it met the untethered spec in 1954 it was handed over to RAE AeroFlight for the research programme to be carried out. RAE tp Sqn Ldr R A Harvey became the project pilot - probably late 1954 or early 1955. Later after AeroFlight moved to Bedford Sqn Ldr Stan Hubbard took it over. The only fatal (Wg Cdr Larsen - OC Flying at Bedford) happened in the tethered gantry and was the result of circumstances I would not like to go into here.
As to why the throttles were rotated up for more thrust why not? Only helicopters hovered in those days and so the RAE specified that type of control (lift your left hand).
Later when Hawkers got in the act trying to do a military aircraft NOT a research vehicle (see Camm letter) then the Harrier type throttle box seemed a better way to go.
