its always ymmv
Tell me about it! When I go to Israel for their annual hockey tournament, I have no problem checking my hockey gear as my 1 free bag and getting to check my sticks for free (per AC policy sticks don't count if you have a bag checked).
Of course, on the return I always have to get to the airport 30 minutes earlier so I can argue with the Israeli AC agents about not charging me the extra $100. I always win in the end, but it's always a fight because they don't know their own policy.
In the meantime, they haven't (yet) measured my bag and noticed it's big by a few cm.