After this last test, I feel prepared to say that you cannot change ETC Angle Error by manipulating the throttle body Effective Area and Predicted Angle tables.
Changing them in the way I describe above definitely changed the throttle response character. It was okay, but I think I prefer the original data.
Looking at a long log, I see no significant changes to the general trend of ETC Angle Error.
Check out this snapshot: both tables point to this angle, effective area, etc vacuum combination being correct. Yet, the angle error of 3.2* is like 23% error.
Attachment 81569