...playing good tunes too fast is "like roller-skating through the Louvre."
Isn't that the truth? I love Altan, but sometimes they play stuff incredibly fast. For example, I much prefer Matt Molloy's version of Drowsy Maggie to Altan's, mostly because of the more relaxed pace in Malloy's recording. (They play somewhat different versions of the tune, but it's really the pacing which makes the biggest difference to me.)
Some tunes sound really good played quickly, though. I really like Altan's "Tommy Peoples" set on Local Ground. "Harvest Home" and "John Ryan's Polka" also sound good when played really fast, I think.