Thanks to all for the above info, I definitely appreciate the advice. Here's what transpired and it may be of interest to anyone troubleshooting a similar problem:
In a series of events this week, the horn is working fine once again without being touched. Seems I had a bit of an electrical problem, the root cause was traced to what seems to be a bad wiring harness for my Gerbing heated gloves. It evidently had a short in it that started dragging the battery down. It's relatively new and didn't give me any trouble the first week, but in the last couple of days the bike became sluggish and slow to start; there was nothing much else evident to point to a battery or charging problem since the headlights remained bright (probably due to the H4 relay kit mod from Eastern Beaver). Although, on the very last night I did notice some vary faint flickering in the intensity of the gauge display.
When I got home that night the starter would not turn the engine over, this was after an hour commuting home, when it should have had a nice fresh charge. I also lost heat to my gloves on the last day or two which was a clue. So I decided to remove the last thing I'd added; after removing the heated gloves wiring harness from the battery, she started right up! I reinstalled and removed the harness twice more to be sure. With it in place, the engine would barely turn over and would not start. With it off, bike fired right up. Nuff said.
Unfortunately, even though the bike started just fine after that, the very next morning it would barely turn over and not start again. Knowing it started just fine 10 hours earlier, I reasoned that the battery was no longer holding a charge, and I'll bet the flickering I noticed in the display on the prior day was likely due to an intermittent short in the gerbings harness, which looked like it helped kill the battery (the battery is almost 5 years old and 40K miles anyway, so...).
To make a long story just a tad longer I replaced the battery with a fully charged one the next night, bike started up instantly the next morning (it almost started before
I hit the starter button, I swear!) , ran very strong all day, and the Stebel Nautiless is back to tooting louder than ever.
So I guess it also doubles as weak battery and intermittent short detector. I'll give it some routine maintenance as outlined in some of the posts above as a way to reward it for trying to tell me something was wrong.
Gerbings has pretty good support and a new harness is being sent out. Can't fault 'em, stuff happens.
Thanks for the tips.