Islam critiqued has a condition; Obsessive compulsive calumnies?

In answer to the video "Muhammad, Psychology and Satan"

The obsessive compulsive opponents of Islam sometimes humourisly project their own condition upon the prophet. He used to repeat certain things therefore he must have had some kind of disorder. This charge is based on ahadith where the prophet instructs people to repeat certain things 3 times, like knocking on a door. There is nothing special about the odd number 3 but it is commonly understood even nowadays that knocking once, twice or 4 times isnt a proper way of announcing oneself at someone else's home. This instruction also teaches to not remain too long outside a person's home since that person might have his own reasons for not opening the door or answering back.

Just as there are no OCD symptoms with people writing children's books and stopping at the number 10, the same is the case for most people counting until 3 before starting something, jumping etc. It is only if one focuses on a certain number(s) that erroneous conclusions are drawn. The prophet repeated, and asked people to repeat certain things a variety of times, 1, 2, 3, 4, 5, 6 or even 20, all depending on appropriateness, common sense, educational or preaching purposes, or cultural understanding of his time.