I was wrong. The failure point was not in the connection proper, but inside one side of the connection at the crimp/wire junction.
I first found out about this when the bike just quit in heavy traffic on a very HOT and sticky day. The battery was DEAD DEAD DEAD. I let the bike cool down and the battery came back to life just a tiny bit. I had to call the GF with a pair of jumper cables and after letting the Miata charge my battery I had enough juice to limp home.
I tested all the components. The Stator tested out totally fine with no grounds, consistant resistance on each coil and 65v (+/- 1) phase to phase through all 3 coils. But the old R/R was bad. So I ordered one from Rick's for $120
The new R/R is on the left, the old Honda OEM on the right
I decided to try an experiment and put the new R/R up where the factory horn used to be under the steering head. It required some re-wiring of the harness. When I tore apart the old harness I was shocked by how cobby it was.
I pulled out the crazy wiring and upgraded the wire size, as well as re-routed the grounds to eliminate as much resistance in the circuit as I could. I even replaced the chincy main fuseholder with a heavy-duty one that uses the larger Maxifuse fuses. I still kept it at 30A though. It's just better/heavy-duty than the crappy one that Honda put on there.
Here is a near-final view of the R/R in its new, cool-air-flow location.
While I was re-doing the wiring harness. I eliminated the crazy flat-bulb holders from Honda with standard automotive lamp holders. Eventually, I plan on getting LED's for these and they are much easier to find/cheaper in the standard automotive base. I also rewired the rear blinkers with dual-filament bases so that the blinkers are now running lights. I like being seen from behind. Being able to buy replacement bulbs for the bike at any hardware or auto store is nice too.
I've got a kuryakyn LED voltmeter coming soon so I can watch the new R/R as well as the rest of the charging circuit, and see if my new location helps any. It still runs hot, just not fry-an-egg hot. When I'm moving I'm sure it will be even cooler.