Hmmmm...

I like mine to sink and I use Orvis Mud or Zink PLUS a fluorocarbon tippet to get it to sink.

IMHO, when the tippet is below the surface film, it isn't as visible and doesn't appear like a line on the mirror-like surface.

I have no issues with my sinking tippet pulling my dry flies under. I do have an issue with a sinking leader butt pulling my fly under on the pick-up so that part of my dry fly leader floats.