10% is awfully high by today's standards. You may want to ask him if he does the traditional cut (to the dentate line) or a 'tailored cut' (to the top of the fissure). Most just do the tailored now and this lowers the risk of incontinence substantially.
I take Miralax and magnesium supplements and really don't have to watch my diet for the most part because of that.
Have you found the ointment to help? Some find that one type doesn't work for them and then try one of the others...