[Mike]

I’m sure that dodgy version of the BBC logo came about in the ‘TV Logos’ font which did the rounds in the early days of TV Forum. I think it was also responsible for the crummy recreation of the YTV chevron which appears on things like Redbubble t-shirts and even Wikipedia…

en.m.wikipedia.org 

Yes, I still to this day have a copy of it installed from whenever I first downloaded it (and it's survived god knows how many new PCs since), some of the logos are spot on but as you point out the YTV chevron, the BBC logo, the Central and Carlton logos are all slightly off. Close enough I'd imagine in the days of 800x600 displays and no real smoothing.

I still wonder how it became prominent across the BBC though, pretty much all BBC Birmingham network production started using it around 2006/7 time.

I must say though, the worst implementation of dodgy BBC logo goes to this:
tvark.org 

The first two blocks are fine, but the final one and the C glyph is not only the wrong weight, but also around 3 pixels too high.