I don't think so, there are no medical study (@others: CMIIW) if floaters are really able to sink down through time. If you still can live with them, there is nothing wrong to wait and keep hoping.

There is already same thread talking about this too:
http://floatertalk.yuku.com/topic/4540/Floaters-can-they-settle-down#.U2iup1d1BSF
A nightmare for someone with a floater directly in their line of sight :)

It's great that you can still put a smile after that remark. I also have a crystal worm shaped floater that like to move to center of vision. When it occured, it put me to a great distress. Even when they were mild, I never find delight from them.