I realized that the cron functions of a XenForo installation won't trigger on time if there are no visitors to a web site, which makes sense I guess because it would require the index.php script to executed in order to see if there are any cron entries to run.
To force the cron events to fire, can I just set a "real" cron to visit the web site during down time to make sure those cron activities get fired when I want them to?
Crontabs in shell are the only way to go as far as I know. Or maybe you could have another web service ping your website at regular intervals but that again would be using cron tabs to implement something like that.
Well, no, that's not it, the cron process it just hitting the defer.php script, it doesn't have any connection to the add-on running, which should be the web server user. I'll have to just shut up and dig into it some more.