Sadly, this isn't accurate. The new jury will be given a summary of all the evidence and testimony from all previous phases. How they will get that summary is still a mystery. I think AZLawyer said elsewhere that this summation alone may take 2 weeks. By witnesses? Stipulation? Dunno......
The summary is essential. No, this is not a retrial of the whole shebang, BUT:
1. The law allows jurors to find mitigation in ANY evidence/testimony from ANY phase of the trial. They have to have access to all of it to weigh mitigation.
2. Mitigation also can be found in the "circumstances of the crime" as well as CMJA's "character" and " propensities." Ditto needing access to it all.