Riemann Hype or Hypothesis?

h/t to William Wu for pointing out a recent (April) submission to arXiv.org from Mingchun Xu (professor from South-China Normal University), claiming a proof of the Riemann Hypothesis (…in 7 pages no less!):

http://arxiv.org/pdf/1402.5952v2.pdf

Such Riemannian proofs show up from time-to-time... my impression is that they are usually sincere attempts, but dispatched with in fairly short order. Have seen no commentary or other news about this particular one on the Web, so don't know how seriously it's being taken -- but not really expecting to see $1 million from the Clay Institute change hands anytime soon. Also, don't know anything about the author, nor understand the paper's content, but Gary Davis tweets me that "such weak tools will not prove" the Riemann Hyp.

This all makes me a bit curious to know if there is any consensus as to which RH "proof" from the past might be considered to have been the most promising, or alternatively, which proof withstood the longest scrutiny before succumbing to a discovered flaw? Any ideas?

In other matters, h/t to Colin Beveridge for passing along this 3 7-month-old Jeremy Kun mini-rant on high school math teaching (it again fleshes out the same idea Keith Devlin and others have pushed):

http://j2kun.svbtle.com/you-never-did-math-in-high-school