Lovebown said:...IT IS common to play ballads rubato. ...saying that playing a ballad with a steady pulse is "harder" than playing a ballad with a good rubato feel, is not true IMO.
I typically hear rubato-type stuff in the beginning and ending of a ballad, if I understand correctly the term rubato. I don't really consider that common. But I do consider it noticeable, and I like to attribute it to groups that have either been around for a while together and have a bond of some sort, or are really good listeners, or both...an option for advanced players.
I remember seeing a West 54th Street Session on PBS with Brandford Marsalis and his group, where they played a song that didn't ask for a beat and tempo that stayed static. Branford tried to describe it as an opera song, where the singer calls all the shots and the orchestra must play follow-up. Maybe that's akin to rubato, I don't really know, but the rest of the group played follow-up to Branford's lines, all schmaltzed up and romantically delivered. It was pretty darn cool.