Ever heard of this?

[RoadRaven]

My LBS (Hi Chris!) says "The device she speaks of was called a " Tire saver " mounted to the brake caliper using a spring piece of wire (generally made from a bicycle spoke) to constantly brush the tire tread in hope of dislodging glass slivers and the like before they could penetrate all the way to the inner tube."

Ok... so they brush the tire... constantly, to dislodge glass etc...

Then how does this work >

But they work, and don't drag on the tire.

If they brush the tire, they must cause some drag on the tire... yes?

[Ninabike]

They can be bent and adjusted so that they float ever so slightly above the tire (distance about the width of a business card).

[sbctwin]

My 'sticker flickers' rode just a hair above the tire. They were flexible enough for me to bend them around the tire, but they didn't 'rub' the tire. They would 'flick' the sticker (goat head) before a revolution of the tire, hence not lodging their prickly little thorns to cause damage. I had them in the 70's ...