I will bump warhost's post because it is excellent and deserves a friendly answer from Jason himself, rather than some buzzphrase?
"I have 3 questions:
What is the purpose of this file?
Is it possible to get rid of it? For some reason it contains personal data of the admin, why is that?
How can I optimize the delivery of this file, such that it doesn't block the whole page from rendering?
While I cannot say that in our case it's slowing down loadtime it IS causing issues on more pages than initially found - initially I reported somewhere else in this lovely forum "only on and below membership options page", which turns out to be wrong for an unknown reason. Unknown because the link to Jason's article I posted there suggests it gets ONLY loaded in such case, I understood?
Frankly, if Jason doesn't have a chance to see this thread, and soon, we gonna have to file a ticket, so important it is.