A session missed withhold is anything the PC thought but didn't tell the auditor. That is fins for the session, but in prepchecking, you want meat, not skim milk. You want meaningful acts. It isn't necessarily antisocial or unmannerly acts like masturbation or nose-picking -- embarrassing acts -- that you are looking for. What you are looking for is overts, not just seamy withholds. There is a difference.
[Comments on the above TVD]
You can have a chain based on a not-knowingness, even if there is nothing there to be not-known. This isn't common. [Missed withhold of nothing.]
You never give up on the fundamentals. When the PC gets nattery, he has a missed withhold, whether the natter has any basis in reason or not. Not many. You audit by those. You should get your own reality on this. It can be crammed down your throat, but it is better understanding, since a stable datum fixed in by a confusion and not by understanding isn't available in a tight spot. This leads to auditing by being reasonable. Fundamentals are meant to be used. If I tell you something is a fundamental, don't just believe it is. Find out if it is or is not in your own universe. It will be, but if you never find this out for yourself, You will just keep going on by rote and ritual. If you do find this out for yourself, you will not need all your old stable data or superstitions.
"What I expect of an auditor is to audit the PC that is right there in front of him by the most fundamental fundamentals that he can command and understand." He will always get wins that way, and he won't be in a fog about any of it. He will be able to evaluate importances in the ritual.
In prepchecking, your "What" question will often miss the mark by a bit, because, after all, until you have done the prepcheck, you don't know exactly what the chain is. And if it is that unknown to the PC, how could you know all about it before you found out from the PC? Besides, all basic incidents must be unknown at least in part, or the chain would blow. Auditing by fundamentals, you know enough about the chain to formulate a "what" question that will come close enough to get what you need. As you go earlier, you find yourself asking about similar things, but not the exact same overt at the earlier time. You get a "what" question that describes the incident in workably general terms and go from there, hoping for the best. All you have to null is the incident that you got the "what" question from.
Prepchecking is not an exact activity. It depends on the PC in front of you. Because it is inexact, you must do it in the framework of total exactitude that is given in Model Session, TRs, metering -- all your fundamentals that must be known solidly. When you have that, you can play by ear with confidence and results.
Any craftsman can create the illusion of terrific ease and offhandedness. However, the common denominator of all great art is "a great ability to do a small detail." If one tries to shortcut the ability to do the details and just does the offhanded action, the result is slop. An auditor's tiny details consist of the meter, TRs, Model Session, etc.
How do you get to be a superb auditor? By knowing all these small parts perfectly. If you find yourself wondering about any one of them, you must practice, drill to get it straightened out. You can go over these items and ask yourself if any of them have been shaky in recent sessions, and work on what you find. Don't let embarrassment stop you from finding out [what needs to be worked on]. Only when you have mastered the detail will you be free to audit the PC in front of you. You won't be free to audit the PC in front of you as long as you are enslaved by "don't knows" among your auditing tools, because you get a chain of error that mounts in She session, based on the basic not-knowingness.
Don't think that you will get results, real, honest-to-God results, if you are anything less than a master of the craft. That is the discouraging point of auditing. The running of repetitive processes without attention on the PC, hoping far the best, does make a lot of people well, as does engram running. This could get long-time auditors stuck in a win. But we haven't had techniques prior to 1962 that reached all cases. We have them now, but they require precision auditing, a master's touch. You have to find out that the technology we have does give the PC wins. You find that out by auditing and seeing the results. If you know all the parts: TRs, metering, Model Session, etc., then you can audit by fundamentals with confidence and ease. There is no more tension.