Obi, I agree with everything you say and I add I have no experience with any radial other than the P&W 985.
I do not ever apply full power straight from a start up but I am also sure it could be done without hesitation. My engine book states that I can do it. I don't.
I believe the cowl flap closed to assist warm up is a waste of time and detrimental to flat engines because they are air cooled and closing the cowl flap with no real airflow through the engine (stationary) will result in uneven cooling. No data sorry, my plane only has ground adjustable cowl flaps. The pilots that I see advocating this are doing nothing more than guessing (if it is not in the POH) and if I recall correctly both the 206 and 185 POH's state cowl flaps open for all ground operations.
Here was yesterday courtesy of an engine monitor.
Start up at 10C
1000 RPM for 2 minutes while seat belt is fitted, oil temp 50F, CHT's through 150F
Power up to 1500 to get moving on long grass
Taxi 600 metres. CHT's now approaching 200F oil at 60F
Run up and cycle prop, CHT's now approaching 300, oil at 70F
Check idle then take off with CHT's around 300, oil at 77F (still below green arc)
At 500 feet, CHT's around 340 and oil suddenly at 120F (well into the green)
I suspect my oil temp sender is where the coldest oil is.
Most engine problems that occur before TBO relate to cylinders, induction systems and turbochargers. The bottom end of most aircraft engines is pretty bulletproof apart from the odd lemon like the 320 H2AD which had a propensity to gall camshafts. Other problems are from lack of use like rusted cams or cracked cases due to too many overhauls perhaps. It is my theory that a flat engine is ready for takeoff power once the cylinders are around 300F.
It is my aircraft, if I was operating yours I would do exactly as you wanted as opposed to "Aussie Bob theory" which is all it is. Works for me. I was going for an annual by the way, all cylinders were good and there was no metal in the filter.