You are basing this on what? Idle speculation?
Having replaced batteries more than 1 or 2 times for a single, still useful laptop. Even if their claims are true the machine will outlast the battery.
Speculation?
History. https://support.apple.com/ibook_powerbook/batteryexchange/
Dude, seriously, if you are on that long of a flight, you should take some time to relax, have a few drinks and take a nap. Nobody should be expected to "work" on a plane the whole time. Unless if you are a chronic workaholic with no life, you should not be working through the flight and your employer should understand that.
That, my friend, would be why you are using an Apple, whereas serious business users use PCs. Because you think that it is up to you to tell consumers what they need and how they will use it, instead of the other way around.
Let's organize this thing and take all the fun out of it.