If you are qualifying and certifying in-house welding inspectors, the minimum test score required to pass is a decision you make. If you want the inspector to be AWS certified, it's a decision AWS (QC1 committee) makes.
As for separating the two committees, i.e., qualification and certification, I understand (third hand) that the AWS was convinced by an individual that was on staff that it was a requirement. Now that the individual is no longer with AWS opinions have changed, but the system is already in place.
My recommendation has been that AWS always ship both standards together. I don't know that staff has been adopted that as standard practice.
One of my concerns is that the problem doesn't show up with just B5.1 and QC1. It is a problem with all of the qualification/certification programs offered by AWS. You need two documents to figure out what has to be done to become certified by AWS. In one respect is is good in that a company can adopt the qualification document (BX.X) and set up an in-house program, but the individual that wants to become AWS certified is left scratching their noggin wondering what to do one they read the B document. They may not understand there is a companion document explaining the AWS certification scheme.
Contact Miami if you are interested in participating on a committee. They have a form for you to complete and it gets directed to the appropriate committee for consideration. Each committee has a designated number of committee members, so you may not get on the main committee right away, but you will most likely be asked to serve on a subcommittee. Currently, I am looking for individuals interested in serving on a couple of my subcommittees: Certified Welding Technician and Certified Welding Educator subcommittees. Remember, you have to pay for your own travel, lodging, and meals. AWS pays for nothing, unless you are in Miami and they make a coffee pot and tea available.
Best regards - Al