what does acceleration use? Is the acceleration of the servo always the same in low, med, and high position? If the pot says its at 1 degree but the servo thinks it should be at 1.5 does the servo respond the same acceleration as if it was supposed to be at 90? What if its making a small compensation near an end point?

You are partially correct. The load does increase the current but most of these servos dont have a current loop to add friction current to acceleration current and then math it out when at velocity. Someone determined a range of masses and did some testing to understand how much more or less current to use for small deviations, large deviations, and constant velocity.

If you are lucky there is a lookup table that creates a couple different acceleration/deceleration ramps like you can see in some servos when the reach the end point. You might also hear the term feed forward model but its fundamentally the same. No matter what somebody took a guess at the acceleration current to add to the work current so that it can be taken back out when you hit the end point. Testing or a guess or whatever doesnt account for the servo being in a mechanical system that is under or over the range that the model was designed for.

im not trying to throw dirt on guys that took an educated guess on how much current to use anymore than Im saying guys misapply products. But both situations exist and if you understand you can make a better choice or even control the variables yourself and screw it up or make it really good,

Ive taken probably 10000 guesses at current for work, acceleration, positioning and synchronization and they werent always right so I might be insulting myself more than anyone. Its just some foundational info to help someone make a decision about what to think about next.

However it is true that some servos always accelerate at max available current and max current is available at constant velocity. Then someone took a guess as to what position to slam the brakes on. Which is still an educated guess to minimize damage to the gear train and not under or overshoot the end point or neutral point.