It would be useful to have a way of adding CSS classes to the trackContent class.
For example,
_paq.push(['setTrackContentClass', "an existing class on the page"]); //to rewrite the TrackContentClass
and
_paq.push(['addTrackContentClass', "an existing class on the page"]); //to add a Class to the TrackContentClass

This way we can add contentTracking without adding CSS classes to the HTML.