My two birds also have different flying abilities. Birdie is a great flyer: she can hover like a humming bird or helicopter, stop on a dime in mid flight to change direction, and dive bomb like a fighter jet. The only thing she cannot do is fly backwards. On the other hand, Verde is only so so. If she wants to fly upstairs, she needs to make two stops along the staircase while Birdie can do it non-stop.
I read somewhere that if you want your bird know how to fly, before you clip its wings you should let it learn how to fly first. When its flight feathers grow back, it will still know how to fly without banging into walls.