Actually, a great tactic. I learned this in a management class on how to interview. If you are vague enough, the person will become confused and just start to ramble off stuff and views on certain items. The last juror was smart, he would ask them to "give him an example" putting the ball back into the DT court.
I know it is hard to believe, but I think the DT is smarter than they would like us to believe. Maybe not in terms of case and the actual law, but definately when it comes to overall "people skills" and relating to the layman. I think that is why JB wanted a minority bunch. He would be able to relate to them on a personal level in the trial, and he could confuse everyone who did not understand the technical stuff and laws.
Believe this happened in the Brad Cooper case in regard to technical aspects of computer and phone evidence.