It's as good place as any to ask. I have edited out most of the quote from your post but you are bang on correct in all of it. The downwind loss of height and into wind turn ballooning are all caused by the model pilot!

The dreaded downwind turn does not exist in full size flying. Since an aeroplane is an aeroplane regardless of size, what applies to full-size applies to our models, and vice versa. But, in full size the on-board pilot has an airspeed indicator and altimeter to tell him he is right or wrong in how he moves the controls. Model pilots have no such luxury. When turning downwind we see the model appear to move fast towards the top-side of the model as if we had pulled hard back on the stick, due to the wind effect relative to the ground. This fools many fliers into easing off the back pressure, the nose drops and the model loses height as it comes out of the turn. On turning into wind the opposite happens, the wind drifts the model towards its belly giving the visual illusion that more up elevator needs to be applied in the turn, so some fliers do and hey presto the model is climbing by the time it comes out of the turn.

In full size, especially when I flew gliders in thermals, I have sat there going around and around and around in a circle for up to 10 minutes, while drifting downwind. The speed never varies, and the height (or rate of climb) never varies. Once locked in, the ailerons are neutral, the rudder stays where it needs to be for balance and the elevator stays where it needs to be for that speed in the turn. Apart from seeing the ground appear to drift, you would not know that there is a wind.

Any model that climbs or dives when turning is the victim of its pilot who is responding to a visual illusion.

Harry