I'm guessing you've already found the best source
for WDW performance information -- Steve Soares'
"Walt Disney World Entertainment" website.
For anyone who hasn't seen this invaluable site,
the link is:
http://pages.prodigy.net/stevesoares/
As you've pointed out, the information here is for
one current week only, so it wouldn't necessarily
be accurate for future trips. But, per information
posted by Mr. Soares, "The schedules don't change
much from week to week, so if I don't have the dates
posted that you're looking for before you leave, you
can still use my site for planning."