I wonder if the signs had to be re-done after someone pointed out that they will (in the future) be in breech of legislation because the Irish was not first and was not given equal prominence to English. It's just a guess though. Someone on boards.ie has a photo of one of the signs and pointed out the problems with it. He said he was planning on complaining about every authority that disregards this (fairly pointless) piece of legislation.
If I didn't know your background I'd think you were nuts believing something like that; but knowing your expertese in this specific area it really does show how stupid most legislation is. In terms of DCC it wouldn't surprise me if they observed this act and ignored the hundreds or illegally errected billboards all over the city.
Stephen I had to pinch myself not to use similarly choice wording upon reading the quote above.