Even if you release multiple times every day, refusing to release on Friday still makes sense. It's not about expecting bugs, it's about guaranteeing that your devs' time is their own. If you aren't okay with paying your devs for time they spend dealing with their own problems at home (without charging them their PTO time for it!) then you shouldn't be okay with making them work on weekends, no matter how rare it is.
The author ended up creating a strawman. Allen's argument was pretty clear: if your deltas are small and your deploy system is fully automated, then no one should be afraid of the risk of deploying.
Given that, if I deploy on a Monday morning and there is a bug on the new release, you revert, reproduce the issue in staging and push only new code when it is fixed. Same thing if I were deploying on a Thursday afternoon or a Friday at 7PM.