Is simple carbs necessary after training?
* No. Not necessary, but helpful.
** Oatmeal and protein shake is fine.
*** MRP, weight gainer or plain old protein shake is excellent. Fast absorbtion, especially with whey. Make sure you eat some carbs with a protein drink though, or there is a possiblity of most being oxidised by the liver. A mix of simple and complex carbs is ideal e.g. fruit + oatmeal + protein shake = excellent choice.
This however, is just post training. Make sure the rest of your diet is as kick ass as the post training meal.
**** don't eat fat with your post workout food. Try and chose food sources with little fat. Fat slows the digestion process down. You don't want this when you want all the good stuff (carbs and protein) getting digested quick for recovery.
Is that enough?