I agree entirely with what BizJetJock has said.
The older iron I spent a lot of time flying had really awful manufacturer's checklists that weere not designed using ergonomics, rather they were compiled as the test pilots discovered they'd forgotten something. RVSM? It wasn't even a gleam in the manufacturer's eye when such aircraft were born and I've seen at least ten different ways of satisfying the requirements - none of which are sponsored by the manufacturer. One operator I flew for was still using QFE for approach (and I believe still does, but it's been a while since I saw a copy of their OM); every other operator I worked for changed to QNH many years earlier.
OPCs also include use of company paperwork, such as the flight log/OFP/plog - call it what you will - and load sheets; the only identical ones I've seen between two companies were ours, and a copy of ours nicked when one of our bods went to head up a new outfit. He even copied the (deliberate) spelling mistakes in the Ops Manual, which when read in order spell B*stards. Bit of a give a way, that, but I digress...
Last edited by Sepp; 12th Jan 2017 at 16:46.