It’s very hard to drop a bearing tip down from your hand onto a small spot, and almost impossible with a fixed tip. The tops start to wobble and bounce and just not cooperate in general.
This trick allows you to control the top and direct it precisely where you want to place it. With a fixed tip, you want to start with a really fast spinning boomerang so you don’t scrub off too much spin while it is in the bind, but it will spin a surprisingly long time.
