The difference here is that very very few people will care. We're talking about mailing in a DVD on Friday, and getting the next on Tuesday instead of Monday.
My solution to this is, don't make Saturday a day when you expect Netflix to be doing anything. My watching days (barring postal holidays) are Tuesday and Friday. I watch the new movie Friday evening, get it to the mailbox before Saturday morning pickup. That leaves Saturday in the hands of the US Postal Service; Netflix gets it on Monday and sends out a new one that I get Tuesday afternoon.
Wednesday-Saturday also works -- they send it out Friday, you get it Saturday (with the added bonus of having Sunday to watch it if you don't have time Saturday), put it in the Monday morning mail to go back, they get it Tuesday, and you get your next one Wednesday.
Either way, as long as you're not expecting Netflix to be moving discs along on Saturday you can still watch two a week.