I realize you are joking but the relentless clash of "thinner" and battery seems to inevitably culminate in the battery getting jettisoned. I mean, we just rationalized the headphone jack getting jettisoned on arguments like "antiquated/outdated." Well guess what is an OLDER technology than that headphone jack?
And Apple seems to be "innovating" heavily around the idea of add-on stuff (sold separately of course) to deliver what used to be built
inside... so why not eject the battery and then sell small ("thinnest"), medium ("thinner") and larger ("thin") add-on packs so that people "can get whatever amount of battery they want."
Apple would get their 5 seconds at the big reveal to spin "thinnest MB ever" AND the increased revenue on each MB transaction since pretty much everyone would need to buy a battery pack of some size. Make it so that the pack must connect via a proprietary, patent-protected jack so that only Apple has supply for the first X months the new MB is out... and licensing keeps third parties from being able to roll out much cheaper alternatives.
Of course, with iPhone Apple learned they can eject that thing and raise the price, so why not eject this thing and raise the price? And they learned they can make the thing ejected connect via a proprietary jack for anyone that wants the functionality that used to be built inside, so Apple gets paid (extra) either way.
Bad dream? Or "the future" coming to Apple laptops near us all?