Barnaby

Not from experience, I am whole enough to report. What brought me to this realization, was when cleaning my chain with a cloth just before the chainring, I managed to get the cloth pulled into the ring, and twice nipped fingers as well. On a fixed-gear site, someone mentioned that you could identify old track guys by their nipped off tips of fingers due to this practice. Someone as well posted a picture of a severed thumb lying on a white and red cloth that were the result of chain cleaning a fixed. One reply to this grizzly picture was that we should avoid cleaning a moving chain in the nude. I think this would have great resonance for men since the jeans zipper is already given great respect, but in comparison to this the chainring on a fixed would be likened to a wolverine. I guess though if you like to run a chain through a cloth, you could do it at the bottom of the ring instead of the top, and the chances of the cloth carrying your hand to the cog would be lessened.
Of course there would be one advantage of the mishap should it happen-it would enable you to stand alot closer to the urinal. So there are always pluses and minuses.