During the ER CC Elon mentioned that Model X reservation holders do not have enough information to know how right they are to have made the reservation (my paraphrase). There were previous hints from Elon about the second row seats and autopilot driving from the highway ramp on to ramp off. So the question is what else was not even hinted publically that makes reservation holders so right without knowing why? I believe that upgraded battery and drivetrain might be just this missing piece. So the fact that there was no any public mentioning of this before does not make this speculation less likely to become reality. If anything, I would argue the opposite is true, as explained above.
I have included snap shot of the page that you referring to only as a point of clafification for the wording used by CS. The actual page that was quoted in the original post by BlakeGallagher was specifically referring to introduction of the Model X in 2015 (see snapshot below)
The AWD design that was optimized to have neutral effect on the range, as mentioned by JB, is not in any way linked to the capacity of the battery. The CS report specifically talks about increased battery capacity - "cells that are 10%+ more energetic"
If it hasn't been mentioned then it is the literal definition of speculation even if it's well-reasoned speculation. For the record I agree there's a good chance Tesla will bump battery sizes with the MX launch but it's also quite possible they won't, so we shouldn't proclaim it's a done deal already.
The CS snippet is in the context of margins, referring 10% more energetic per cell (not necessarily 10% more energetic per pack).
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yes, the question was asked about the GF, but as I hear the answer, the 10-15% chemistry improvement would be in the GF cells, but the first use of the new chemistry wouldn't necessarily be with GF production.
question is at ~25:20 http://www.media-server.com/m/p/bbz2caea
Good catch... I can't listen again right now, but the impression I had was it was all part of the ongoing improvements to the pack (A, B, C, D packs MS owners are reporting)? I could be wrong, but I think it's not necessarily a step change with the MX introduction, although it would make a lot of sense to introduce a step change at the same time if it's ready.