I've been reading about these , counter bands, on the friendly narrowboat do dah on that FB thing and I thought what a load of fetid dingo's kidneys. As for making your self more visible in tunnels really. Steamers had counter bands and I would have thought that, 1) all the smoke would be a clue that there might be a boat ahead of me and 2) I would be unable to see the boat ahead of me because of all the smoke etc. 3) and as diesels motors took over from 'orse boats and steamers they often boated with a butty so you still would not be able to see the counter bands. 4) I don't think that the old paraffin lamps would be able to shed more than a modest glow lighting up the tunnel walls either side of your stem so it seems unlikely that they pick up the counter bands of a boat in front unless you were right up to their tipcat.
And lastly I would have to be so close to the boat in front of me in a tunnel to see the counter bands that I would be able to see the boat anyway.
If they were really there as some sort of safety feature why did not the 'orse boats/butty boats have bright flashes on their arses.
Just asking that's all.