I spent much of my year as lobby chairman in 2003-04 in talks with 10 Downing Street trying to prevent briefings going on screen. Not because we were defenders of an outdated, archaic system, but because lobby journalists at that time believed readers and viewers were better served by the system that currently exists.
Experienced and respected journalists are able to ask the Prime Minister's press secretary questions behind closed doors that could never be broadcast because of libel laws. It is pretty effective when the Government is under real pressure, and readers and viewers are genuinely better served by their correspondents tackling issues head-on with a spokesman who doesn't need to clam up because the public is watching.
Those who argue it is a block to transparency are mistaken. Televising the lobby daily would turn into nothing more than a bland press conference.
Put lobby briefings on camera and the only information you would get would be a pre-cooked announcement from the PM's spokesman or the unfortunate minister lumbered with the job.
The novelty would wear thin pretty quickly - and it's questionable for how long broadcasters would carry them.