I would prefer you to answer why it matters so much to you to try to minimise the whole topic by focusing on that one word, pinprick. Out of all the facts about FGM, above every mind-bogglingly disgusting and unimaginable truth and detail about it, you want to reduce the discussion down to the issue of a pinprick compared to everything else that is done. 
It also doesn't state that the prick is done by a pin. A prick done 'correctly' could destroy all sexual feeling and even destroy the look of the clitoris.
I didn't know that a prick on the clitoris was now part of the categorisation. However, I do know that the minor forms of FGM are actually very rarely done. Furthermore, what you might be unaware of, or wilfully overlooking, is that 1) 2) & 3) and sometimes 4) too are usually done together, or in some combination.
As for the other things done apart from pricking in level 4, then yes, they are pretty horrific. And they do compare to removal of the penis head and testicles, because the nerve endings for pleasure are in the head of the penis, and scraping, cauterising, incising, piercing, and even pricking if done harshly enough, will destroy the clitoris enough so that the victim cannot feel any sexual pleasure. After all, a boy with the head of penis removed will still be able to urinate. In most cases of FGM, the victims aren't even capable of urinating normally, due to the mutilation, so even then, it would be worse in that sense than the headless penis. The things done in level 4 would also affect the look of the genitals, making them not look like normal, identifiable genitals, so yes, that is comparable to removing testicles. And labia, etc., do play important part in sexual and general health function (such as distributing essential lubrication and keeping germs out, and so on, so yet again, comparable).
I have answered you, even though it should be fairly obvious to anyone with even a passing knowledge of human biology, ot ability to perceive medical implications, etc., why even Level 4 FGM is still appalling. Now please answer me, explaining why you are so invested in derailing the topic by focusing on one small thing I said that could possibly, on superficial viewing, be undermined by a single word on the matter. Why do you NEED FGM to not be as bad as it is?!