What's not clear about it? That's the idea.
they are indeed a significant problem
Only if there are better equilibriums which can be moved to by attacking sunk cost - otherwise they are simply the price of doing business.
(I only found two studies bearing on it, neither of which were optimistic: the study finding sunk costs encouraged coordination and the bank study finding attacking sunk cost resulted in deception and falsification of internal metrics.)
I just finished the first draft of my essay, "Are Sunk Costs Fallacies?"; there is still material I need to go through, but the bulk of the material is now there. The formatting is too gnarly to post here, so I ask everyone's forgiveness in clicking through.
To summarize:
(If any of that seems unlikely or absurd to you, click through. I've worked very hard to provide multiple citations where possible, and fulltext for practically everything.)
I started this a while ago; but Luke/SIAI paid for much of the work, and that motivation plus academic library access made this essay more comprehensive than it would have been and finished months in advance.