first, you say mass - you mean weight.
No, I do not. The scale you're standing on does not provide an output in Newtons. Sure, it does achieve it by simply dividing the measured force by a constant, but it nonetheless attempts to measure mass.
Using your example on RET, a good one for our discussion by the way, my weight (again due to gravity as defined by newton/einstein) on the scale would reduce when you cuddled me and tried to lift me up...but YOUR weight would increase by the same amount mine did (if you were also standing on a scale). this is all well described by gravitational forces.
Correct, but irrelevant. I'm not standing on the scale, and neither is celestial gravitation.
well then my acceleration has not been decreased and therefore my weight hasnt been impacted. This is because acceleration is the square of velocity, not a force.
This directly contravenes the equivalence principle.
Does this explain the conflict in UA more clearly?
No. I can see that you're missing something, but you're too busy trying to explain why you think you're right for it to be particularly clear.
I
think this may be your mistake: You assume that if an object falling towards a mountain top is accelerating downwards more slowly than the same object at sea level, then the mountaintop itself is also accelerating upwards more slowly. This is simply not the case. If we use the Earth as the frame of reference, there are two forces here - one downward one, which will be identical in both cases, and one upward one (celestial gravitation), which will be greater at high altitudes.
Moving back to an external frame of reference: it is not the case that the Earth is accelerating upwards more slowly in these places. The object in question is also accelerating upwards (at a greatly reduced rate) due to celestial gravitation. Therein lies the difference.