No, it depends,
Steve Nash does it by what he calls drippin' in the cookie jar by pointing his fingers down which is good but i feel that if you want to have the perfect smooth touch you need to use the index finger along with the thumb and the major and just flex to the max your wrist while keepin' your fingers a
little sloppy. Practice, Practice, Practice
Watch Ray Allen's hand and wrist. in that video:
http://www.youtube.com/watch?v=6IPuD8bGdts
Keep going