At the risk of following up to myself (one foot in internet hell!), having done another little investigation, here's what I found.
The code responsible for the check-new command is in browser.c, in functions _mutt_select_file (public) and examine_mailboxes (static). examine_mailboxes ultimately passes the job to mutt_buffy_check, but calls the latter with the force argument set to 0, which means nothing will happen unless the mailbox checking timeout has expired. Since this code executes in response to an explicit user request, this seems strange. What is the reason for not passing force = 1 here? -- Please *no* private copies of mailing list or newsgroup messages. Rule 420: All persons more than eight miles high to leave the court.
