Help requested in identifying a possible symptom of OCD

So I have a friend who has some rather strange habits that are really an entirely different discussion, but he has a specific habit of capitalizing letters in words in text messages where it's not in any way called for, and once when I made it a point to comment on it and point it out he actually said he felt compelled to do it (or along those lines though I do believe he used the word compelled) then changed the subject. Here's an example of one thing he said just today:
ME: Where you watching the game? At Joey's house?
HIS RESPONSE: My Mom's.. He waS gonna come here but he went to hiS Sisters..
Where you @ ?

Note the capitalization of the letter "S" at the end of these words. I can post many more examples if necessary, but anyone have any thoughts as to whether or not his odd spelling compulsion may point to some OCD?