Typos are the bane of the printer - a folkie in Birmingham worked for a printer and they managed to get their business cards wrong - ooer. But cross referencing is automated in DTP apps - that is just finger trouble, brain fade, sloppy and ultimately always with us - especially in software. Look at Micro$ft Windows.

Then there is the Grauniad. And the Telegrope (up market UK Newspapers)

And then there is the wind assisted spool chequer - someone else who can't spell, but thinks they can, adds all sorts of erroneous speelings to the dicksionary of "Word" (etc) and the next users who know they can't spell trust it.

It's a jungle out there.