The Berglas Effect (if I'm not mistaken) is David Berglas's ACAAN. Sure there are other ACAANs out there, but Berglas's is the supposed "holy grail" of ACAANs, and I'm pretty sure it is called the Berglas Effect. I've never heard anyone use "The Berglas Effect" as interchangeable with "ACAAN". An ACAAN can be any ACAAN, but the Berglas Effect is David's ACAAN, which is the most famous and "legendary" ACAAN out there. Also, anyone who owns the book The Berglas Effects (released recently-ish by Richard Kaufman) knows the method of David's ACAAN. He teaches it in all it's jazz-magic-ness.