Years ago the firm I worked for changed their health insurance provider forcing us to choose new doctors in a different clinic system. My wife was looking through the bios of the Doctors within the system and asked me who I wanted...I told her to look for the Doctor with the smallest fingers.
The last time a doctor performed the procedure on me, I related to him how painful the first time it was done on me by another doctor. This doctor said the first time he had it done, the doctor who performed it was a big guy with huge hands. You can imagine the result.
Moral of story: always have it done by docs with small hands.