So you have see this happen often with the SL's? What can one do to prevent lever hang ups on these particular brakes? I have these brakes on my bike and will add this in to the maintenance with some advice.
The carbon levers have a tighter tolerance in the lever body than the aluminum ones. You can either switch the levers to aluminum, or take the levers out and take a file to the little bushings on the sides of the lever.