You have an intriguing question that could probably be best answered by the Honda Customer Service people, whose phone number can be found in your Owner’s Manual. My best guess is that there is a misprint in the manual.
However, what would concern me much more than an issue of exactly how much gas that tank can hold is your own statement, to whit:
“the third time I decided to cram as much in as I could, and put in 11.95 gallons – a full gallon-plus more than the specified tank size.”
In case you were not aware of it, doing this is what damages the carbon canister that is the heart of your evaporative emissions system. Hopefully, one incident will not kill the canister, but I can assure you that repeated incidents like this will kill that canister–without which you cannot pass state emissions tests.
Although I can’t tell you what the replacement of a Honda carbon canister would cost, I can tell you that on Toyotas, replacement of that canister, with labor, tends to run about $400.00–and this is not covered by any car maker’s warranty because it constitutes owner negligence.
Traditionally, Hondas have no room left in the gas tank when the pump “clicks off”, and while you should not attempt to force more gas into the tank on any make of car, I believe that this practice would be particularly injurious on Hondas, due to their tank configuration. Let’s hope that you have not already caused damage and that you will heed my advice for future fill-ups.