All sources should be questioned, and you have the same ability to question sources as do others on this site to make sure the information being used is as valid as possible. I can provide numerable examples of where men and women who barely deserve the credentials they have got media time (such as the "Liberals are smarter" thread, made by the man who "proved" beautiful people have more girls). This is how it is in the real world and otherwise when dealing with sources, including the academic and scientific communities. It is a source of contention within parliament at the moment that the person who wrote the report is not exactly unbiased and should be mentioned here as well.
Likewise, questioning sources goes well beyond bias. For example, the media fails to correctly report on such things as margin of error (there is only 75% confidence on some methods/stats used in this report, and that does not mean that the entire report has 75% confidence but far less, this is basic statistics) and also fails to note the massive amount of shortfalls noted by the writer of the report himself, save for the odd article. Therefore, both sides are making some overstatements as to the level of confidence they can have in this report in parliament, forgetting the great deal of time the PBO who wrote this took in listing the problems with any cost estimate, including his own.
As noted in the report itself, there is a remarkable lack of information to draw information from. I mean no offense, but I can see why the Conservatives are questioning some of the assumptions made after reading a good portion of the
report myself. Likewise, I can also see why the opposition can make some comments about the reports they have received as well. Things are far less definite than they appear to be through parliament debate and media reports in this case for all reports and for both sides.
This gentleman could very well be right and the costs may reach this level. However, that does not mean that it should be taken at face value from the get-go, as the PBO himself, who wrote this report, says. That the level of confidence in this report is generally so low and that there is a dependence on many assumptions does make any report, from this gentleman or otherwise, somewhat questionable. This should not be ignored and passed off as a typical CKA action, but taken to heart as important in all discussions to make sure you understand as much about the source as possible.
We can demand all the reports and contrary information we want. The title of this article is, however, misleading. The price has not skyrocketed, it's just forecasted to potentially have a higher mark with a specific set of assumptions made which are not agreed upon with all parties. These are the facts.