When hair is tied freestyle it is done in such a way that the hair should be able to be freely styled in any direction.
So yes you can comb and style it any way you want to with no problems.
The downside is that the knot is not as secure as say hair tied in a specific direction.
The reason being that to be able to achieve the uni directional attributes of the hair, the knot is slightly looser in construction and if done correctly and handled with care then there is no reason for it not to last as long before shedding or dryness of hair renders it unusable.