you know, there could be something to it.

i fish without an indicator, mostly because the fish i go after are spooky, most of the time. whenever ive used an indicator, i have caught noticably fewer and smaller fish. i thought they had become "wise" to what an indicator was and just closed up. but considering the waters i primarily fish, the theory makes sense. with several different surface currents at any time, it is certainly expected to have differing under-currents, and perhaps it is this causing the fish to turn down nymphs when using an indicator.

definately a good point, and something to consider when im nymphing.