I think this was the telling part of the article:
So, Lukacs and Johnson filed a complaint with the Canadian Transportation Agency, and things started to get weird. They asked for a copy of the reimbursement policy Air Canada had quoted in denying Johnson's expenses. Air Canada objected. The airline would only disclose the policy if Lukacs and Johnson agreed to sign a confidentiality agreement. Public disclosure of a document detailing how stranded passengers are treated, argued an airline lawyer, would put Air Canada at a competitive disadvantage.
Johnson refused to sign. But Air Canada had filed the policy and a supporting document with the CTA, which Lukacs promptly posted on his Air Passenger Rights website.
When is a policy not a policy?
Air Canada then proceeded to argue that, in any event, the policy is not really a policy, even though it is titled "Expense Policy" and Air Canada staff had described it to Johnson as not just a policy, but an unbreakable policy when they denied him full compensation. In reality, argued Air Canada, the policy is just a sort of internal guideline, some suggestions for staff, and it doesn't stipulate absolute limits, and therefore it conforms with the Montreal Convention, so Johnson's complaint should be dismissed.
"It's a policy unless it isn't, and we'll decide when it is," is how Johnson put it to me, with a typically military ability to distill the essence of a sprawling rule.
We sure do know one thing though, if this all goes pear shaped for Air Canada, which is entirely possible, then AC will be looking for new lawyers and better legal advice than they are currently getting! This expensive public relations disaster and legal misadventure is just the sort of stuff that ends up becoming ammunition for proponents of industry regulation.