I know that nobody in my Fundies class knew how to frog kick, or back kick; I don't think anyone had ever shot a bag before. Several people had not air-shared with a long hose before. We got taught how to do those things. There were a lot of land drills and in-water practice.
I think Dave's criticism is apt IF you are determined to pass the class the first time through. It is very difficult to do that, if all the material of the class is new to you. Four days is better than the three we had, but it's still not enough time to take a relatively novice diver and introduce her to a bunch of new stuff, and expect her to polish it to GUE passing standards. But if you have a local instructor, you can get your provisional (which is what you will get, so long as you have a good attitude and are trying, and the instructor doesn't think you are grossly unsafe in the water) and come back after some practice to get your pass. It took me 6 months to get my rec pass, and another year plus a bit to get my tech pass.
This becomes problematic for people who either have to travel a long way to take the class, or are flying an instructor in at great cost. This leads to the phenomenon of people trying to learn everything that is in the class from somebody else before they take it, so they can just march through and demonstrate what they know and get their pass to go on to Tech 1 or Cave 1. It's not a good use of what are usually some very good, talented and motivated instructors.