I think the jam-up was worse the weekend before, actually. We arrived the Sunday before and that Sunday and Monday were horrific in the MK, IMO. Admittedly, we got out of there Easter Saturday so we weren't there Sunday.
The irony of this whole thing is that the real bottleneck is Casey's. Always has been, and there's no real way to fix that without a second gate or by exiting folks through the parking lots.
Nothing they're doing is going to address the bottleneck at Casey's as far as I can see. Like I said, I don't think they can from a practical standpoint. It's going to be interesting to watch. Everybody that enters/exits that park has to walk down Main Street and disperse/come back together (basically) at Casey's. I don't see how the mods are going to help anything really but we shall see.
I think the concept is that remodeling the hub will encourage people to move the break-away point further towards the castle. Personally, I don't see it happening unless they close the walkway leading to Tomorrowland and the bridge by Crystal Palace. That's the only way it will ever work and even that creates a whole new set of problems, IMO.