If I may, I have issue with the notion that penalty phase and mitigation is a "personal" thing and jurors can just come up with things. It IS personal, but personal to the extent that it has to be FROM EVIDENCE presented, and it has to be SUBSTANTIALLY PROVEN, MEANING IT IS MORE OFTEN TRUE THAN NOT TRUE. Let's say some jurors took the text message as verbal abuse...okay that's fine...they are SILL not done though...it has to be SUBSTANTIALLY PROVEN. Did Travis verbally abuse Jodi more often than no?? I don't think so.
According to the "capital case instructions of 2011" from the Arizona Bar website (I couldn't find the specific ones for this case and didn't have time to mull around for it):
"That is, although the defendant need not prove its existence beyond a reasonable doubt, the defendant must convince you by the evidence presented that it is more probably true than not true that such a mitigating circumstance exists."
"More probably true than not true" is NOT the same as "Did Travis verbally abuse Jodi more often than no?? "
As I understand the instructions - the number of times doesn't matter, the question is "Is it more probably true that Jodi Arias was abused(during her lifetime) than not."
I can see how from the evidence presented, some might come to this conclusion.
As for the "personalness" of the decision -
"A mitigating factor that motivates one juror to vote for a sentence of life in prison may be evaluated by another juror as not having been proved or, if proved, as not significant to the assessment of the appropriate penalty. In other words, each of you must determine whether, in your individual assessment, the mitigation is of such quality or value that it warrants leniency in this case...
In reaching a reasoned,
moral judgment about which sentence is justified and appropriate, you must decide how compelling or persuasive the totality of the mitigating factors is when compared against the totality of the aggravating factors and the facts and circumstances of the case.
The "moral judgement" to me makes it a personal decision by each juror.
The information presented here from the Arizona Bar can be found at:
http://www.azbar.org/media/58847/4-capital_case_instructions_revised_2011.pdf