I didn't say that Irish music lacked rhythm, just that it puts more emphasis on the melody. The decorations in Irish music are there to embellish the melody, whereas the decorations in English music tend to emphasise the rhythm.

As a player, I know that my enjoyment from playing Irish tunes comes from being swept along by the melody, whereas the enjoyment from English tunes comes from getting into the rythmic groove and seeing where it takes you.