Stan, your contributions are appreciated but please do not criticize those who suggest improvements.
Anchoring regular expressions (that don't start with wild-card) is a must to avoid false matches. This is a correctness issue. Matching "To:" just because it appears in a Subject: is wrong. Savings in CPU cycles come second. The best way to save cycles is to group patterns with the same prefix under IF/ELSE/ENDIF. Wietse