Yes that's right muscle growth takes place when you rest not when you workout, so protein when you rest is just as important as on the day you workout, personally i have 3 protein shakes a day, 2 of those are 1 scoop and my post workout is 2 scoops so 4 servings total, and on the days off i have 3 single servings spread throughout the day.
You've got it right with the 2 scoops after a workout though as its important to take advantage of that window when your muscles are drained and a big 40g serving of protein is ideal.