"Ironical"?

Reading a case recently (LePage's v 3M), I noticed that the dissent used the word "ironical." Now, I always thought this wasn't a real word. But, according to dictionary.com, it is. See here.

Interestingly, the definition listed online contains the following fascinating usage note:

"The words ironic, irony, and ironically are sometimes used of events and circumstances that might better be described as simply “coincidental” or “improbable,” in that they suggest no particular lessons about human vanity or folly. Thus 78 percent of the Usage Panel rejects the use of ironically in the sentence 'In 1969 Susie moved from Ithaca to California where she met her husband-to-be, who, ironically, also came from upstate New York.' Some Panelists noted that this particular usage might be acceptable if Susie had in fact moved to California in order to find a husband, in which case the story could be taken as exemplifying the folly of supposing that we can know what fate has in store for us. By contrast, 73 percent accepted the sentence 'Ironically, even as the government was fulminating against American policy, American jeans and videocassettes were the hottest items in the stalls of the market,' where the incongruity can be seen as an example of human inconsistency."

A quick Lexis search shows that "ironical" appears in 350 state and federal cases, including a bunch from the Supreme Court. I guess that means it really is a word. Or if it's not, I can't fault an appeals court for using it - after all, they're just following precedent.