Too Many Temperature Sensors! How to ignore them, and thereby not clog event Database?

This is totally inaccurate. After you get to 1000 events for an attribute, the number of events in the backup will be constant. It will be 1000. Because that is the number of events that the system keeps. Whether those 1000 are from 1000 days or 2 days, that is the max number of events that will be saves for each attribute.

Correction: Now it limits the database to 100 events as of 2.2.3.