In the QA pdf no. 4
Q: Can a Cavalry Column participate in a Major Battle? Surely they don't split into two Wings with no centre.
A: Yes. The three wings would be an abstraction in this case but for the limited number of times this will occur, it does not make sense to create a whole new combat procedure that would basically work out to the same result.
Does this mean that Cavalry Column indeed distributes its forces evenly between three wings? I don't really understand the answer.
Edit: Now that I think about it again I suppose it means what I just said.