The pdf also has "Téacs" for every chapter whereas it should read "Ceacht", according to Doyle's audio. There are a few other places that don't match up as well.

Yeah, since I only transcribed the reading texts, I changed the header from Ceacht to Téacs. I have the second edition, if there are some other mismatches in the texts (didn’t listen through it all), I wonder whether the text changed between the two editions (the second one was published in 2005, so presumably after the recordings were made).

(…) Yes, the altering of Ua Laoghaire's Irish was a quibble I had - you just can't do this. Should I teach Shakespeare translated into some other form of English? You can't do that. But it is churlish not to admit that, apart from being in Polish only, this is very near to being a perfect textbook.

I’ve found this edition of Mo Scéal Féin published by Brún agus Ó Nualláin with author attributed on the cover as Peadar Ó Laoghaire – https://www.siopaleabhar.com/tairge/mo- ... -athlaimh/ – which seems heavily ‘standardized’ from the scans on siopaleabhar, eg. ar Ghaeil (instead of Ghaelaibh) or fé chosa a námhad. I think they might have just quoted directly from this version (so the fault here might not be theirs… or it is, but not in ‘standardizing’ but just by choosing this particular edition of the text – though I can’t confirm it’s exactly the same as the passage in the textbook).

But I find it likely, since they seem to list this edition in their reading list recommendation in a footnote on page 18 (“P. Ó. Laoghaire, Mo Scéal Féin, Longman Brún agus Ó Nualláin, Dublin”).

B’fhéidir go raibh an Ghréigis ní b’fheárr ná í nuair a bhí an Ghréigis beó agus muíntir na Gréige dhá labhairt, ach ní raibh ar mo chumas‑sa an chúmparáid a dhéanamh ach amháin idir mo Ghaelainn bheó féin agus an Ghréigis a fuaras in sna leabhraibh; agus chómh fada agus ’ chuaigh an chúmparáid sin bhí an bua ageam Ghaelainn féin. Is dócha go ndéarfadh duine a tógadh in áit eile, nú i gcúig’ eile, in Éirinn, an rud céanna i dtaobh Gaelainne na cúige gur tógadh é féin ann. Ach tá roinnt nithe againn chun an scéil do bhrath. Sarar fhágas‑sa Lios Caragáin níor airíos riamh amach a béal duine na habartha so, .i. tá mé; bhí mé; bhí siad. D’airínn i gcónaí táim; bhíos; bhíodar, &c. Nithe beaga is ea iad san, ach is nithe beaga iad a thagann isteach go mion minic sa chainnt. Agus is slacht ar an gcainnt an módh dlúite seochas an módh scurtha. Ar an gcuma gcéanna, is neamh‑shlacht ar an gcainnt an módh scurtha seochas an módh dlúite. Dá éaghmais sin, bíonn sa chainnt dhlúite neart agus fuinneamh nách féidir a bheith sa chainnt a bhíonn ag titim as a chéile.