It's the not at all part I worry about. On a trip from Newport to Bermuda, I saw some lights on the horizon that were on constant bearing with us. I woke our captain who tried to raise the vessel, which was clearly on a crossing/collision course. Eventually, it appeared he would cross well ahead of us. After an hour or so, a very drunk "captain" got on the radio and told us that he was, indeed, a tow vessel (lights not properly displayed) and that he had a huge barge on 100 meters or so of cable behind him with no lights on it (did I mention it was starless and pitch black?). We roused the crew and tacked off for several miles. The tow vessel finally put a searchlight on the barge, which looked particularly lethal, as close as we were on a blustery night in the Atlantic). I do think this is the exception, rather than the rule, for commercial skippers, but things like this have happened to me more than once and the consequences of them getting it wrong can be pretty disastrous.