Re: DS9, Worf and Continuity.
I think there are several other more worthy 'Worf to DS9' continuity nit-picks than this one. Things like this:
TNG (New Ground): Helena brings Alexander back to Worf on the Enterprise because she and Sergey are too old to handle him.
TNG (Firstborn): Worf adamantly opposes K'mtar trying to send Alexander to boarding school, arguing that his son belongs with him.
DS9: Worf sends his son to live with his now even older parents who didn't want the kid just a few years ago.
Never mind the fact that DS9's Alexander should be the age of, what, like 8? Instead we see someone who looks at the least like a teenager.
I never make mistrakes.