I am not sure if this is still relevant, but I edited the post by Alice025 that BOAC didn't understand to make it more readable. I have to note I am not a professional and do not have all the terminology correct. The sentence I could not understand is in cursive.
Now, BOAC.
You wrote you never told your height to the ATC on PAR approaches, and you wondered why anyone would.
I questioned a military pilot again regarding why he would do it.
He explained that this is the accepted way of interaction with the ATC, i.e. the way the pilot-controller tandem operates.
The example given was landing in 100x1000 visibility.
“The complex preparatory stages in this weather demanded some tricky flying. The first step was getting to the point 52 km away from the aerodrome and at 4,800 m height. Then from this point descending to the next point at the slope of 30 degrees and speed of 550 km/h. When approximately there (by flying time), telling the ground control my height - and as a return courtesy the ATC responded with the plane's distance to aerodrome.
Desirably, the distance is set for the second point. Also at that time ATC told the pilot by how many degrees and in what direction to turn to finally get on the landing course and that is where ATC gave permission to descend.
When ATC allowed me to let out the landing gear and the flaps, I needed to descend at an angle of 12 degrees and at the descent rate of 30 m/s to proceed to the next point where I needed to be at 2,000 m height. In this mode the ATC periodically told me where to fly to get on the landing course and I simply told him my height in response as a confirmation.
When 30 km away from the aerodrome, I could finally breathe out, decrease my descent rate by half and the descent angle to 8 degrees, but this was still too far from the aerodrome and the ATC still didn’t see my descent path so to their directions regarding where to fly I simply responded with my height - simply called out the number.
In the next stage the initiative in conducting radio-talk was passed over to the pilot.
While before this point ATC saw my deviation from the course and gave me commands to which I responded with my height (which meant "I understood you, thanks a lot")
- then in the next stage the ATC kept quiet unless I told them my height (which meant I want to know my distance and deviation from course).
Knowing my distance I could correct my descent rate up to the point of entering the glideslope.
From this point to the outer NDB the ATC already saw not only my course but where I was in relation to the glideslope and, in general, could do without me calling out my height - but the quickest way to find out my distance for me was still to say my height - as an echo the ATC immediately told me my distance and lateral deviation in meters.
If instead of saying my height I said “Dear Controller, please give me my distance to runway edge and lateral deviation, if possible"
- it wouldn't work out very well.
From the outer NDB to the runway I usually didn't give my height but if I had doubts regarding my position I could say it and the ATC replied with distance.
Of course I had a system to tell me the distance and lateral deviation but it was not always exact and I had to confirm the data by some other means. For the ATC knowing the height is important as they usually have over 10 planes landing at once and have to know who is on what height."