In the case of stuck tunnel boring machines, a good example is the second St. Clair Tunnel (http://en.wikipedia.org/wiki/St._Clair_Tunnel). The Seattle Times has a good article about the problems encountered with the St. Clair Tunnel and how that relates to the Seattle Deep Bore tunnel: "Canada’s tunnel saga offers lessons on Bertha fix" (http://seattletimes.com/html/localnews/2022905964_berthasarn...).
The conclusion of the article nicely sums things up:
> Arguments over costs in Sarnia dragged on until 2008, when the Supreme Court of Canada decided who must pay $36 million for repairs and delays — the CN Railway’s insurers.
> By then, double-stacked trains had been using the tunnel between Canada and the U.S. nearly 14 years, and the seven-month delay was long forgotten.
> Until now.
Now maybe other things will go wrong, and the project really will be a fiasco. But I don't think we're anywhere near that point yet.