Nah, most I've played with actually had a pressure setting bolt, or a spring changed out. More than one spring shown in kit too. Drilling holes is more of a momentary timing and quick/slow pressure rise mod thing, or pressure relief rather than increase. Its' result is usually a TEMPORARY effect. For pressure regulation to the entire trans the effect has to be bigger than that. I wouldn't be surprised if the drill was to open a restriction to those small accumulators to let the errant one fill a bit faster when worn trans is cold. Obvious from kit parts that the accumulators are a heavy wear issue.
Interesting reading the hydraulic flowchart for the trans. There are TWO pressure regulators, a main and one for solenoids A/B. The main one is spring loaded like all, but in this case the EPC solenoid pipes output into that spring chamber to add to the spring's tension and modify the line pressure itself. Simply adding a shim or a stiffer spring would definitely bump up the base line pressure with no added input from the EPC. Line then goes to the solenoid regulator to be modded again and then tees back into EPC input that seems to get regulated by blowing off into space like a regular bypass on an oil pump, just electrically regulated instead of sprung valve. I could not find in/out circuits like the other solenoids have, only in at EPC. A delicate balance going on between line, EPC and sols. A/B...............