Everyone is different.Everyone gains in different ways.I've gotten decent gains on the traditional
I've also gotten good gains on Total Body Training. I prefer total body training.Just because it allows me the days to work in some GPP and other training.If you can gain doing 5 total body workouts a day,then do it.So much of the lifting is trial and error.You gotta take the info on this site and apply it to you.
As far as the pros and other guys from the past training two-three hours a day..well just because it works doesn't mean its optimal. I myself try to keep my workouts 45-1 hour just because thats where I've had the most success.