Longman Dictionary of Contemporary English (so well used that the cover, and date, are missing, but definitely late twentieth century, and very useful for providing American variations) under 'careen' has only one meaning:

verb esp. AmE [=American English]: to go forward rapidly while making sudden movements from side to side.

Nothing about boats at all.

Q has posted a relevant message on the "threat to the English language" thread, quoting similar uses.