Tommy,
I'm pretty sure we are going the same direction here. The question revolves around machine calibration. Most of the equipment out there in the field doing the work on pipelines and many other kinds of work are Lincoln's, SA whatevers. Many don't have gauges to go by. You have two controls for controlling the arc and the volt/amp curve. It's all a matter of knowing how to set the machine in order to achieve the correct results on the inspectors volt/amp meter and comply with the wps in use on the job.
Now, in the shop it can be slightly different with the kinds of equipment in use. Calibration and accurate gauge readings are a real advantage for both the welder and the inspector to do quick inspections with little effort on his own so the inspector can get back in the office and watch his movie, play games, or flirt with some secretary. But it definitely adds to the shop efficiency when it comes to making sure the welders have set all the parameters to the wps. It would not be cost effective to have the shop maint person going from machine to machine setting them. And the inspectors would always be complaining about the work not being correct.
Quick note, now, the comment you quoted from me referred to having the correct amperage regardless of the gauge, not just whatever suited you. Though I understand, many of us have our personal 'sweet spots' and it also combines arc length which will alter volts and amps. Both SMAW and GTAW, even FCAW and GMAW. No two welders, person or machine, truly run 100% the same even when wire feed speed and voltage show the same. But that's one reason why manufacturers spec and wps's have a 'range'. Even if the wps is very tight, there are still applicable tolerances before you are out of compliance and have to have another one.
Anyway, I really do think we are on the same page here, just using different trains of thought trying to say it.
Have a Great Day, Brent