The Toronto Star's Antonia Zerbisias explains why the 7:45 p.m. EDT broadcast turned into a 7:02 p.m. EDT broadcast.

An excerpt:

Here's how the networks' commercial considerations changed the national agenda.

For Steve Wyatt, Global's senior vice-president of news and information, the "BlackBerry madness" erupted at 4 p.m. Wednesday when the PMO put out the e-flash that took Ottawa by surprise.

Wyatt was enjoying a beer in a Las Vegas airport before hopping on a plane home to Vancouver when his Toronto bureau called, saying the Prime Minister wanted network air time. Wyatt was not impressed: "My immediate response was, why would we do that?"

Why indeed?

At that time, Global's got Joey, the Friends spin-off, in a "pre-cast" that beats the clock on NBC's telecast at 8 p.m.

Okay, so it's not the greatest-performing show on TV. But it does help deliver an audience to the much bigger simulcast with CBS at 8, Survivor: Palau.

Simulcasts add tens of millions of dollars to a network's bottom line because they theoretically double the audience's chance for catching a show.

But the Canadian Radio-television and Telecommunications Commission stipulates that for a simulcast to pass regulatory muster, the Canadian broadcast must start exactly when the U.S. feed does.

If the Prime Minister would drone on too long, or if Joey was to stretch past 8 p.m., Global would miss its simulcast window for Survivor.

There were other considerations for the private networks besides commercial realities. CTV News's president Bob Hurst (Note: If you don't know, I'm a CTV News employee:

Hurst still feels the sting from August 2003 when during the hydro black-out, the networks heard from the office of then Ontario premier Ernie Eves.

"Sunday morning, they tell us they need to go on for important public announcements and the premier needs to address the province and he wants to do it 6 p.m. that night," Hurst recalled. "So we got in a conference call and we asked all the questions. Is it a public safety issue? Yes. Is it an emergency? Yes. Is it a political speech? Absolutely not.

"We gave him his 10 minutes. It was a political speech. We offered up Ernie Eves on the promise that it was an emergency public issue and we did not provide the Opposition leaders an opportunity to respond.

"And we felt burned."

There was no way the networks would let that happen again.