The line diameter does seem to make a difference on getting your stuff down quicker with less lead, I like to fish as light of lead as possible and still get my bait/worm/yarn where it belongs and keep it there as long as possible, just bouncing along the bottom, you can *almost* achieve the same thing with heavier mono and heavier lead if that is what you like to do, though, you do wind up with more of a dragging rather than drifting drift and line stretch and belly will work more against you than for you, especially noticeable on longer casts.

Try PP and pencil lead instead of slinkies when drift fishing.....the difference in the feel is insane.