Absolutely not. It sounds like somebody needs to have a talk with this guy about the headphones and a few other safety issues. He's going to hurt himself and/or others at some point.

On that note, we had our first paceline accident at last night's tire ride. Tire contact. Three riders down, one with a broken collarbone and one with a bad cut on his arm and a carbon bike that's toast. It was a sobering reminder that pacelines/group riding can be dangerous. It's not clear whether anybody was riding recklessly last night; it may have just been a bit of bad luck.

In any event, I've thought twice about pointing out bad habits before to other riders. I've decided that I need to be a lot more assertive in that regard.