[Si-Co]

This Channel 4 Ident from their excellent optical illusion era was never used on-screen. A shame as it's a good one. I think it's called Drunk Man.

youtu.be 

This seems very long to be an ident - the “4” doesn’t appear until about 40 seconds in - perhaps that’s the reason it wasn’t used? Or it was an early “cut” and would have been re-edited or remade if it was used.

Yes, I'm not a huge fan of it either. It also doesn't quite fit the structure of the rest of the set, in that the blocks have to deliberately move to make the '4' form-up and then move away to break it up, rather than it being a camera angle thing that means that the '4' is briefly formed.

Perhaps it was never intended to be an ident, but a promo for something or other. Like to say, it’s nothing like the rest of the set.