It's a challenge to determine someone's expertise in ArchiCAD.
We have an internal benchmarking assessment based on ten specific disciplines (eg. modeling, drafting, editing, creating views, layouting, publishing, teamworking, etc). We even use it for screening potential employees.
They must sit a 100 question in 100 minutes written test, followed by a 2-3 hour, 364 point, practical test.
But to even qualify they must first register at least 80% on Graphisoft's
ArchiCAD Competency Challenge. I think that's quite a good place to start for anyone, even if if is sometimes a test in 'Hunglish' more than ArchiCAD!
We have found the results of our internal assessment to be extremely accurate, both with existing and new staff. It never ceases to amaze me how many people tell me they have been using the program for XX amount of years, expecting that to qualify them. Often that just proves that they've been using it incorrectly that whole time!
Hope that wasn't too tangential to your question.
Cheers,
Link.