The double Irish isn't a competitive tax rate. It is a tax evasion scheme. Just some links I found quickly:
http://www.nytimes.com/2014/10/20/opinion/ireland-still-addi... http://www.irishtimes.com/news/politics/abolition-of-double-...
http://www.nytimes.com/2014/10/20/opinion/ireland-still-addi... http://www.irishtimes.com/news/politics/abolition-of-double-...
This got announced at the last government budget - I could not make any claims about the economic repercussions one way or the other.