Why Does Transmitting a Trial to Several Other Courthouses Throughout the Country Materially Increase the Risk of Witness Harassment?

As I understand the procedural posture of the stay application in the Prop. 8 transmission case, the only thing the Supreme Court was actually considering was whether the trial may be transmitted live to five other federal courthouses throughout the country. The question whether the trial may be distributed to the public via the Internet was not before the court, because “[a] final decision whether to permit online publication would be made [by the Ninth Circuit] when technical difficulties were resolved.”

If that’s so, and the transmission will be seen only in several other courthouses — as opposed to throughout the nation on YouTube and in excerpts replayed on TV news — then why is there reason to think that such a transmission would materially increase the risk of witness harassment (see pp. 12-13 of the majority opinion)? The transmission would, of course, increase the size of the audience, but no more than holding the trial in an extra large courtroom would. And most of the extra audience would be far from California, and therefore not especially likely to be able to effectively harass the witnesses in ways that turn on seeing the witness’s testimony. (Some audience members might harass witnesses by, say, threatening a boycott of their employers, but that would be equally possible based on newspaper coverage of the trial, without regard to whether the trial can also be seen live in several other courthouses.)

This is not necessarily dispositive of the bottom line, since the Court’s chief argument is that the district court’s order violated federal notice-and-comment law; that would be true regardless of the breadth of transmission. But I take it that it would affect the balance of hardships, which is relevant to the question whether the Court should stay the district court order. That, I take it, is the argument on p. 8 of the dissent. Is the dissent correct on this?