Generating tests to simulate thousands of end to end transactions per second isn't trivial, and simply generating the load isn't the issue. You have to generate the load, create random queries, random transactions, random latencies, all the while maintaining a deterministic design in your tests so bugs can actually be investigated. Sure, Disney could have spent millions creating a test infrastructure and delayed this by months, if not a year, but they're being smart with their money and leveraging beta tests in a real world environment. That's smart management.
This has already been delayed about 9 months.....it was supposed to roll out in October.
I've done it successfully on less $$$, with sites getting many tens of thousands of hits per minute.
I can't agree that this is a smart management decision, not with Disney's past record with information systems. They are taking the cheap path, plain and simple.
This system is going to limp along for years and never be quite right, just like all of their other systems.