Dealers of merit that I know could identify without any hint 95% of my coins to the level we see on slabs. I occasionally buy from but would not expect to liquidate through someone who can't tell an Elagabalus from a Caracalla or a Pertinax from a Septimius. Same for a Spes from a Salus (or a few dozen others). I expect professionals to know more about coins than I do. It would be an interesting exercise to separate all my coins from their tags and see how many I could reunite correctly without using a reference. Obviously I would have trouble with some of the Septimius types that I have in a dozen examples. This is not a question that will be answered. I'm not that curious.