True. It's 7 years old, and I push it to the limit. I'm normally running apps to use 99% of processor time. One important app that is usually running needs to have 90%+ of processor time available to work well. The avast processes in Web Shield only use about 5-10% of processor time during a download from the internet, but that's too much for me.
I'll test the other Exclusion entry format with a wildcard * at the end, as you suggested, after awhile... I need to wait for a big download to complete first, which I don't want to interrupt.