This was extremely helpful, saved me a lot of time.  We had an issue where some standard change templates were being misused by end users who were using a saved URL to open the standard change, even though the user criteria of the template excludes the user opening the change record.  I used this to create a business rule to block insert of the change if the logged in user does not match the User Criteria on the applied Standard Change Template using the getMatchingCriteria function.  This ensures that users cannot erroneously open a standard change using a template that they do not have the proper matching User Criteria.  Thanks for sharing this info!