'The thing to keep in mind is the split between what is the Judge and the Jury are each supposed to be doing.
If it's a matter of "the undisputed facts are this, how does the law apply", it's something that the Judge is supposed to decide.'
This case is complicated by the fact that the Judge is deciding *which* fact the jury will be evaluating. And that decision will often decide the outcome.
Also, this case raises a tricky issue. In court, the structure of the trial is supposed to ensure that all evidence will be critically examined by the opposite side. That is *not* the case for "evidence" introduced by a member of the jury during deliberations. Of course, you can't prevent jurors from introducing their own knowledge and experience. However, I think this case (if yokem_55's statement about the jury foreman is correct) demonstrates that the in court portion of the trial and jury deliberations need to be more interactive. For instance, if the jury foreman introduces "facts" from his own experience, another member of the jury should be able to ask questions of the judge or counsel.
In general, I don't see why jurors can't ask questions about facts as well as points of law.