very common
and in my opinion, a very good practical idea.
The Ops Insp, keeps current, on type, but also sees the sharp end of the operation.
The last trip I did ex UK CAA, AOC several years ago, the inspectors report was that he was impressed with the crews understanding of the practical problems associated with the type of operation, and felt he should congratulate the operating crew highly.
When asked off the record, just what he was saying: he admitted: there is no way he would work for the company full time, as they treat you like dogs, but keep just legal.
I did a similar exercise with a GCAA Ops Insp recently. He was shocked at the blatant mis use of the FLT, but the company, but was powerless to place a report on file that criticized the operation. (american spell chequer.!!!!)
Off to India for a session of training next week, and based on my previous experiences there, should be fun.....