The answer, as noted, is that there is no set standard that is required. When I do my classes, the standard I use is "Can the applicant safely load and discharge the firearm." In some cases we know that answer in just a few rounds, and in others we need some remediation/correction.
Clearly more novice shooters have less skills and may need more guidance, while experienced shooters see this as just another hoop to jump through as part of the permitting process.
Instructor's philosophies differ. I do not see the permit class as a "how to shoot" class, and accordingly my classes have a fairly minimal standard...again, are the people safe and can they handle their gun so as to not be a danger to themselves or others. We look at handling, safety etc.; accuracy is far down the criteria in my classes. Our typical class uses just a small 8.5x11 paper, from 15 to 20 feet. Hit the paper on your shots. That is more than adequate for self-defense.
Being a retired lawyer, my classes focus more on the legal aspects...what does the MCPPA allow, what are the rules for carrying, what are the use of force considerations etc. My partners that work with me also offer advance defensive shooting classes as we do feel that is both useful and important, but do not feel that the ability to put X shots in the 10-ring out of Y attempts should be a mandatory qualifier.
It is hard to quantify "reasonable self defense accuracy", but it is all that I require.
The State law just requires an actual shooting exercise. It is intentionally left vague so as to permit individual instructor variations.
The twincitiescarry.com/forum is a good start. Many good people there as was noted.
Paul Horvick
http://shootingsafely.com