Leaf Annual Battery Check vs. Carwings vs. LeafSpy?

I've just purchased a used 2011 Leaf with 11 bars of battery and 25,900 miles.
I've stumbled into the discussion of the "required annual battery check" and thread http://www.mynissanleaf.com/viewtopic.php?f=27&t=17045&p=371939

My question is: what does the Annual Battery Evaluation on a Leaf check, that Carwings does not already upload to the Nissan mothership? Is there anything in a Nissan dealer battery capacity report that I can't get through LeafSpy?
Are there other good reasons to have a 25k Dealer Checkout?

While the annual battery check doesn't give you (the consumer) any useful information it does keep the battery warranty valid. LeafSpy gives the owner real data on the battery.