Can you please clarify why you think YMMV on this one? (doctorofcredit.com)
Let's do some basic math using the Chase Sapphire Preferred as our example since it's a popular card and most reports indicate it's rare to be able to get the second year fee waived on it via a retention call (YMMV as always). (travelcodex.com)
I've previously mentioned the call - in option here and DoC reports that it's still working but very YMMV obviously. (dannydealguru.com)