Hi everyone, I wanted to check a grammar form I came across on Saol ó Dheas recently.
The clip is here at around 1:10 and the speaker is Máiréad Uí Lionáird (Cork native speaker who read the Séadna audiobook) - so I know the quality of the Irish is bullet proof.

Long story short, she says “seo dán a scrígh fear áitiúil ……”.
I was surprised as I had assumed that a form like this should be expressed as “is dán é seo a scrígh fear áitiúil ……” i.e. that we should be using a “sentence of definition” (see Teach Yourself Irish 1951 PDF page 66).

Obviously I’m wrong, and happily so, as the grammar used by Mairéad is nice and simple.
Could anyone help me clarify what’s going on here? I.e would it be incorrect to use a statement of definition (as I have written it above)? Is Mairéad’s form short for “seo é (sid é) dán a …” / “sé seo dán a …” i.e. a sentence of identity?

This is fine. Seo dán -= this is a poem. Seo é an dán - this is the poem.

It is not that common in literature, but Ua Laoghaire has "seo deoch den fhíon is feárr".

Sin is more common, eg sin ní.

Seo dán: copula of classification
Seo é an duine do dhein é: copula of identification

It is also important to realise:

seo (é) = is eo é
sin (é) = is in é
siúd (é) = is iúd é

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

The slight difference between …

"short" forms like: Seo dan a … / Seo é an dán a …

and

"long" forms like: Is dán é seo a … / Is é seo an dán a …

… is not classification / identification (b/c both can be both) but presentation / determination.

The short forms starting with seo/sid/sin/siúd are rather presenting, the long forms are rather determinating.

The short forms could be translated as "Here's a poem …", pointing to it.
The long forms do not point to something but define it (as a poem written by a local) and differentiate it from others.