I seem to remember News expressing reservations about being introduced over some pictures of some people dancing about.
So instead they decided to just have the people dancing about instead. Great move.
Looking back at old clips, the clock gave a much smoother introduction to the news, particularly since regionally produced idents into the news. I always feel, at least in the North West, we crash into it, either hearing a bit of London's ident, missing a bit of the thunderclap, or having a few seconds of silence after the ident. A silent clock is not only more suited but provides a smoother transition.
BBC Midlands seem pretty dead on regarding idents these days. We rarely hear network and rarely miss thunderclaps. I miss little technical niggles like that!
ISTR seeing a BBC 1 Clock in the current style at a major BBC Centre, not used though!
There was also TV Mercia's mock for 2006 too!