I'm sort of shocked I have to refer to anything, this is pretty much standard less-wrong material. This is not 'vaguely' this is pretty much bread and butter. I gave references in my original post(first few chapters of gambling with the truth/any textbook on statistical decision theory). His statement is incorrect out of the box without me being difficult whatsoever.

http://lesswrong.com/lw/gu1/decision_theory_faq/#what-do-decision-theorists-mean-by-risk-ignorance-and-uncertainty