The fact that Boras never even countered the Lerners' 10/300 offer (when Bryce said to get it done) tells me that he felt could probably get something like 11/310 or 12/320 but not hit the record - Bryce gets his mega deal, but it's not a record, so Boras looks bad. It sounds like Bryce wanted to stay at a big contract and could work off 10/300 with deferrals, but Boras convinced him he had to leave.
Also lol @ old man Ted handing over an envelope in a rain delay and then making Bryce charter a plane to come see him. The last offer can only be conceived as a "we don't give a crap anymore if you leave" offer. Offering 12/250 with MORE deferrals is a freaking savage move.