If you look at the press release, people from the study do say that.
http://www.exeter.ac.uk/news/featurednews/title_476860_en.ht...
The study does agree with this, people who sit less die at the same rates in the study. So one assumes they are standing-ish when not sitting and hence standing more won't help you since it didn't help them.
They included some confounding factors like the fact participants where white collar. But the reality is, so are most of HN.
Would really like a reason to dismiss the study but yet to find one other than it conflicts with others and I don't like it's result.