1.  Yes; multiple times.  Events reappeared when I tried this back in May.
2.  Samsung Captivate (AT&T)
3.  No
4.  I first noticed it on May 22, 2011.
5.  When I first noticed this on May 22, I found your troubleshoot idea from another Google Help Forum and all events came back.  On May 24, the events were missing again.  I tried the troubleshoot process again, but events prior MARCH were missing with the exception of recurring events.  I WAS USING ANDROID 2.1 AT THAT TIME.  So I updated to Android 2.2 in the beginning of June (hoping this would solve the problem).  After updating to 2.2, I tried the troubleshoot method again and events prior APRIL were missing with the exception of recurring events.  Since then, I tried the troubleshoot method for the fourth(?; lost track) time and now events prior MAY 17th are missing with the exception of recurring events.  It seems like every time I try the troubleshoot method above, I lose more events. 

Thanks for looking into this issue.