i asked a similar question about a month and a half ago and the response was:
I'm not sure AJK understood your question and/or you understood his answer. An AOR is a bunch of apps (or even 2/3BMs) from
multiple issuers at the same time (within a few hours or same day*), the primary reason for this technique is so that:
1. The issuers don't typically see eachother's inquiries (for apps from this AOR), even when pulling from the same bureau.
2. The issuers don't see other recently approved cards (from this AOR), since they all pull at the same time.
*) As opposed to (for example) three with Chase last week, two with Citi two days ago, and an Amex and Bofa tomorrow