That's right.If your fat intake ratio is too high,you can gain weight/fat.If you want to be "lean",then eat lean.Kind of simple actually.However,if you want to be "healthy",then you need to balance your % of fat intake so that you get enough to maintain your energy levels.
Btw,this metabolism doesn't occur until your body is accustomed to deriving its energy from fats as opposed to carbs/sugar.