That's just perverse. Hornby Dublo 'super detail' coaches were a significantly inferior product to the concurrent Triang 'scale length' ones, which apart from their obvious dimensional superiority and better running were stacked with moulded detail that was simply printed to the sides of the HD toys. Hornby Dublo were a busted flush by that time and barely capable of serious consideration, and that is in comparison to Triang, for pete's sake. Toy shorty coaches, solid cast wagon chassis, underscale length locos, poor lining and finish, overpriced and outdated.
Sorry, I know this is anathema in some quarters, as the truth often is.
Not saying that Triang didn't perpetrate some appalling crimes against scale a very few years later when they thought they had the field to themselves, but the idea that Hornby Dublo products were in any way superior in scale, running, finish, or accuracy is bound with the concept that die cast metal is superior to moulded plastic, which it isn't unless it is done a lot better than HD did it in the 60s.
I happen to agree with you about the livery of SD coaches, but, come on, tinplate? Without separate details? No.