This discussion was started to discuss the standard ABC, so if Sandman is referring to something different we are clearly at cross purposes. And whilst ABC is intended as part of a package of software resources the text language itself does not require a computer, so to criticise it for not being much use to people who don't have access to a computer is completely wide of the mark.

If you're writing music by hand on paper then of course conventional notation is probably the best way. Even so, ABC is handy when you don't have ruled manuscript paper to hand, and it takes up a fraction of the space of the equivalent notation so is much better for jotting down tunes on a beer mat or the traditional back of a fag packet.

Standard ABC (I don't know about the Irish version) represents all the conventions of notation in text form, so to use it requires an understanding of notation. It is simply a different way of representing exactly the same thing, and which you use is a matter of choice. I don't understand your claim that it is "less accurate" as everything in ABC is exactly equivalent to the same score written in notation.   The two are entirely complementary, and which you choose will depend on what you want to use it for.