2 day split twice a week???

In Robert Kennedys enclyclopedia of bodybuilding he says a 2 day split twice a week is the most effective for building mass

But i am confused about one thing how should I order the muscle groups choice 1 or choice 2

choice 1

day 1. chest/back/biceps
day 2. legs/shoulders/triceps
day 3. off
day 4. chest/back/biceps
day 5. legs/shoulders/triceps
day 6. off
day 7. off

choice 2

day 1. chest/triceps/shoulders
day 2. legs/back/biceps
day 3. off
day 4. chest/triceps/shoulders
day 5. legs/back/biceps
day 6. off
day 7. off

In his book he has the first choice listed but i came up with the second choice because alot of people have told me it would be overtraining to do tris and shoulders the day after chest. I dont know what to do now i mean i thought he had enough rest day that it wouldnt matter and also ive been doing what he says and my body doesnt feel overtrained at all. But ive also heard not to do tris and shoulders on chest day as they could lift as much cause they would be drained.