As mentioned, I agree that both AOW and Deep courses can vary some according to the instructor. My instructor for AOW was IMO very good (I had him for several other courses). But our "Deep" dive was to 63 feet. Well, that was where the only boat for a month was going in March on the FL panhandle (there was another group of Vintage Divers who booked the trip, so we were an add on).
From what I recall of the Deep Course (here in Nova Scotia), it was quite comprehensive--mainly because most of the time on the 4 dives we were in the 110-120-130 foot range. We shot a sausage from 120' and reeled it in to reach the safety stop (no easy task in 33F - +1C water --end of May-- diving wet-- only me....). We also did the "square peg in a round hole" task to check narcosis--I don't recall feeling slower at 120', but who knows). Also the crushed pop bottle and floating egg yoke ball, which was neat. Plenty of gas planning. Got to see how fast a tank empties down there. Proper descent technique at 45 degree angle to the anchor line but not holding it. I usually just pull myself down on it head first, but that was good to learn. Don't know what more could be included. There was a (20 question?) written test -- this was 2007