When you work out, the 2 days following to this your muscles will be recovering, after that you don´t have any extra gain from "resting" that muscle.
You're better off doing less volume per work out, and train a muscle group twice a week, than doing more volume and working the muscle group once a week. I'll give an example:
Train once a week:
You might do 5 different exercises for chest, the last 2 or 3 exercises will probably not be as efficient because your muscles are already very exhausted. After 2 days of rest, your chest is basically recovered, the next 5 days don't do anything for you.
Train twice a week:
You will do 2 or 3 different exercises for chest, you'll be able to execute every exercise to it's fullest potential, making your work out more efficient. After 2 days, your chest will be recovered, and you will hit your chest again.
What I do is:
Monday: Chest, Biceps, legs, mid-abs
Tuesday: Back, shoulders, triceps, side-abs
Thursday: Chest, Biceps, legs, mid-abs
Friday: Back, shoulders, triceps, side-abs
Note: Your chest might be a bit sore when you go for the second workout of the week, but as stated in the post you linked to, that's perfectly normal.