Maybe he is talking about himself, maybe he isn't.

It's all surmise and supposition.

Before jumping to premature conclusions, it would be salutary to note this erudite post by Big Tim on an earlier thread about the Ould Triangle

Subject: RE: The Ould Triangle: which gaol ?
From: Big Tim - PM
Date: 05 Jul 08 - 03:08 PM

The song is featured in Behan's play 'The Quare Fellow: a Comedy-Drama', first performed at the Pike Theatre, Dublin, on 19 November 1954. As far as I can trace, the first public performance of the song was given by Behan himself when he sang it on radio in 1952, on 'The Ballad Maker's Saturday Night'. He had been working on The Quare Fellow since around 1945.   

Nowadays, Behan's authorship is seldom questioned, but it is very interesting to note how he introduced the song on radio. "This song was written by a person who will never hear it recorded, because he's not in possession of a gramophone. He's…he's… pretty much of a tramp". Behan was not renowned for his modesty: certainly not to the extent of crediting something successful that he had written to someone else. In addition, his biographer Michael O'Sullivan writes that Behan asked for the radio royalty payment to be made to Dick Shannon, a Dubliner: possibly an old pub or prison acquaintance. O'Sullivan also quotes the show's producer, Micheál Ó hAodha, as stating "he [Behan] never claimed authorship". The 1952 broadcast consisted of only four verses.

The balance of probability is that Dick Shannon originated the song and that Behan later added to it