That is interesting about the coil; I believe there is a simple resistance check for the coil (which I did last year), and I recall it checked okay. Could it see dielectric breakdown under operation, which wouldn't be picked up by such a test?
As for the compression test, the only info. I was able to get (so far) is "200 lbs compression per cylinder."
I will try to find out if they did a leakdown test.
The valves were not adjusted; would this contribute?
Also, the oil I find accumulating is in the airbox (which houses the air filter), and it must somehow be getting sucked to that point through the breather hose which is connected to the valve cover. Is this common or normal?
When cold and starting the engine, without touching the throttle, the engine sometimes turns quite a few times, and sometimes starts right off; regardless, it will sit right at 900 rpm at idle. But, after touching the thottle, and then letting it idle as the rpms come back down towards 900 rpm it will keep dropping towards ~ 400 rpm at which point it starts to bog (you can sometimes hear bearings start to chatter), and then it will climb again to above 900, and will cycle like that. It doesn't do it always, and seems to do it less when the engine is fully warmed up.
I can't tell you how much I appreciate your help.