Roger...the following sentence needs (a lot of) explanation:
"Further checking showed that the years I was using for probability (1997-2001) contained several large quakes with too many aftershocks to cancel out, giving false answers."

Also...you have been back and forth over the months on evaluating Don's predictions...from way better than chance to chance. So, I don't know what to make of any of this. But, I suppose it does not matter whether I don't know if Don's method/ "the data" work...because I'm not in a position to do anything with this...
Chris