I use yarn indicators for steelhead and nymphing drifts when searching streams for the locations of fish. I feel they are superior to thing-a-bobbers for number of reasons, they indicate 90* drift, land with leas disturbance and are much more durable. The color, that find I like the best is white, witch i feel is less intrusive on the water film. When they sink simply dry them out between fingers, puff and preen apart. The addition of a past silicone will allow 2 steelhead flies a weighted nymph and dropper egg fly with about 3 to 4 bb size split shots staggered along the distance of the line being suspended.
the biggest reason they are superior yarn indicators are very simple to make and very cheep.