Pretty much. I think systems like DC training and HIT are far from optimal. Minimizing one of the only variables we can control for progress (volume) is a fantastic way to undermine your goals.
It probably depends. There are also convincing arguments in favor of low volume: http://www.exrx.net/WeightTraining/LowVolumeTraining.html
And I've seen all kinds of bodybuilders being successful with totally different volumes.
The thing is that if you are training with high intensity (percentage of 1RM) then you can't use as much volume as when you are training with lower intensity. So it's kind of self-regulated. The way it works best for me is to do another set for the same bodypart as soon as I can perform at least the reps of the previous set, no matter whether that is in 5 minutes or in 5 days. Obviously, at some point, systemic exhaustion will also become an issue. But until that happens, I let performance dictate the frequency and the volume of the exercise. This way, cycles of lower intensity will regulate automatically to a higher volume, simply because I can do more.
With the above in mind, I have personally seen the best results with daily (or even several times a day) full-body workouts. If I do a set of bench press with maximum effort, the ideal for me is to have another set of bench press as soon as I can repeat the previous set's repetitions. Which may be in 5 minutes or in 2 days, depending on the intensity and the systemic exertion. I can choose to either do full-body, in which case the limiting factor usually is systemic exhaustion, or focus on few bodyparts, in which case the declining performance (in medium intensity) or the stiff joints (in high intensity) are what limits the frequency.
I've been using the terms like this:
Intensity = Percentage of 1RM
Volume = Weight * repetitions * sets
Frequency = How often I train the same bodypart
Duration isn't an independent parameter in this context, it depends on volume.