I am wondering if the 60 kWh offering is an experiment. Maybe they want to find out just what is the incremental addressable market by dropping the prices a bit. Especially now that the Model X is shipping in volume which increases their ASP and with hopefully less problems which increases their margin. Therefore it's time to try out lowering their margin on the base S and see what kind of demand there is at that price point. Cost efficiency of the Model S might have hit a new high, giving them the capability of doing this. Plus, it might shake loose some more Model 3 reservations to commit to the S earlier. Now, offering a lot of options in between confuses the buyer. Ideally from Tesla perspective, the 60 kWh offering gets more people interested, but then more people actually end up buying the 75, either now or later. Plus, they can easily choose to change it to something else, like 65 later on, but I think many options at once would be too confusing. And if they get the vehicle back as a trade in, they get to unlock the rest before reselling it, potentially unlocking a big chunk of the value.