It turns out that the decision to have Sherzer go on the stand, and
admit wrongdoing was quite correct. It was a big risk, but it paid off
for him. By essentially admitting to what the State accused him of
doing, he allowed the jury to focus on the nature of the crime (even
the Prosecutor admitted that Sherzer's actions might be interpreted as
barely legal), and on the entrapment defense. I'm surprised that the
jury bought entrapment, but fortunately for Sherzer the agent was a
bit too energetic in his sting, and it was also clear that the tenor
of the conversation changed in a dramatic way, from when Sherzer was
actually conversing with the girl.

I doubt that the agent will be given another opportunity to do a
similar sting.