You're definitely right in that it will cut down on people taking advantage of the few remaining" free" lockers. Why pay for a locker for you stuff over at Bilge Rat if you can stuff your stuff in a free locker at Hulk and then come back and get it, right? The only thing is they have to make sure this isn't chaos, which I think they can do, but I also think it will be very tough on busy days because of the relatively low theme park IQ of the average guest.
I just figure if the lockers are full they hold people at the lockers, until a train unloads, and then let people in once that group have collected.
But I mean, they probably were able to calculate capacity enough and how long the wait from the lockers to exiting ride would be, to determine how many lockers they would need.
I have a feeling it will be smooth.