I suspect that dog's objection is based on rigging issues. After all, there is only so much one can lash to the end of the mast. Put a VHF antenna, windex, etc... up there and then try to rig an additional three feet of lighting.
I do feel that the all-round red over green supplies the most visible lighting arrangement. Let's face it, sidelights on a sailboat offshore are about as relavent as sidelights on a dredge working the Pawcatuck river; relative to other vessels, neither one is moving very fast. The tricolor has only the advantage of height, which ain't for nothin', but only shows one light to other vessels. And, if that light is red or green, it is not seen at quite the distance the stern light will probably be seen. A sailing light display gets two all-round lights aloft and is universally recognized for what it is. IMHO, that acheives the desired goal of being seen the best possible way.
In port, the sailing lights, coupled with side lights on deck, will be more noticeable than the tricolor as well. In that circumstance it is much more likely to provoke the desired, "what the hell is that, Gladys" response, which, after all, is the most one can really hope for isn't it?
I am a little surprised that none of the light manufacturers offer mast mounted 180 degree lights. Then one could mount two of each colour on adjacent sides of the mast acheiving a 360 degree arc. That would work nicely on a fractional rig.
The Boasun's comments are probably most appropo. Have a flare up light, like one of those million candle-power lamps the cops use to burn through the vinyl of their front seats when they forget to shut it off, is very effective at illuminating the sails, and is recognized as a signal to attract attention. After that, you're pretty much relying on your radar reflector, the sidelights and size of boat dictating that your chances of being seen, in other than good weather, are not too good. Anyone who's gotten into a close quarters situation with a ship is painfully aware of the deficiencies of a two mile visibility light. Two miles is getting right on the edge of damn close, in open seas, especially when there is any doubt as to what either vessel is doing. Another strong indicator for flying a radar reflector, and maybe line drying your cookware as well. (g)
“Scientists are people who build the Brooklyn Bridge and then buy it.”
Wm. F. Buckley, Jr.