I've read a lot of material on how hard-gainers (if there is such a thing) should approach building muscle and one thing i see time and time again is the amount of gym time.

Most books on the subject recommend 1hr of training for 3days a week.
Day1: Chest, shoulders, tri, abs
Day2: legs, lower abs
Day3: bi, back, abs

I was curious if this is the right approach. or if a 4-5 day split would be more optimal for building muscle.

Note: im not on steroids so i cant workout limitless