::Default according to whom?  WP:ARCHIVE still refers to archiving with sequentially numbered archives, and all of the other talk page information I just checked is either silent on the issue or points to that page.  Regardless, I don't see that as the main issue - as I said, I think they both have valid and useful places - since use of Werdnabot is discouraged on article talk pages, HBC Archive Indexerbot would remain useful there even if Werdnabot indexed every user talk page it serves.  My main point still stands, though - silently making it the default, without any type of documentation, is going to confuse people, and potentially cause problems.  I really think it would be in everyone's best interests for it to be a documented option, rather than a default. —