FIXME: This stuff seems too specific for BMO/UserGuide, but it probably doesn't belong all in a generic FAQ either.
Why doesn't mutt decrypt secure bugmail?
Currently Bugzilla uses traditional PGP packaging, which mutt doesn't automatically detect. Try adding the following to your .muttrc file:
message-hook '~s "\\(Secure bug .* updated\\)"' 'exec check-traditional-pgp'
Why shouldn't my component have a default CC list?
When a new product or component is created, a number of questions are asked: Who is the default assignee? Who is the default QA? What is the description of the product/component, etc. One of the pieces of information a component can have is the default CC list. In general BMO discourages the use of the default CC list for new components because the needs of the CC list tend to change over time. People change teams, leave mozilla or wish to cut down on their bugmail.
Rather than use the CC list, the recommended way to track changes in your components is to use Component Watching. The aforementioned link (login required) allow you to watch changes in a given Product or Component. If you have multiple components within a given product that have a common prefix.