I think it's neurological and not fully under her control.  There have been reports that when Hillary goes backstage after a rally, she often immediately collapses and needs to rest and reorient for 20-30 minutes before she can stand up again.  It might explain her very controlled and limited campaign. 

 

I do not like the woman but would never make fun of a serious medical condition if she has one.  Does it affect the campaign, if true?  Of course it does. 

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