A pole too many.

Trampers

My first outing with my new Magnum awning.  Everything okay but I'm left with two sections that obviously belong together but I'm not certain where.  According to the diagram it goes on the front, left hand side of the awning but why?  And is this correct? 
On the Isabella assembly video the man doing the demo does not mention it and it isn't shown at all.  Can any Magnum owners tell me what I am doing wrong or what am I missing here?