I still think locals wouldn't have too hard of a time getting in, the Flex pass is informative here. I think people will reserve without firm plans in place, or if reservations are so hard to procure, the act of reserving will guide that person/family's plans for that particular weekend. I'm not entirely local, but I do speculatively reserve sometimes and fill in the logistics blanks (hotel/airfare) later.
The problem for me with the making reservations is that I have a Premier Pass, so I should have access 365 days. If I have to make a reservation, it becomes like a Flex Pass where I no longer have the level of access that I paid for. Will I get a refund for the difference in not getting full use of my pass? My pass technically expired 2.5 weeks into this so I have gotten full value in my mind out of it, but it makes my renewal options and thoughts different. I would normally renew the Premier as I have(had) plans for WDW in September that I will most likely be cancelling, so I may hold off on the new pass until a time that it will not be so up in the air.