I certainly hope that isn't true, because: Toyota HAS to pay attention to that. It may not be feasible for a few years, but there's no question that Volt has the right amount of EV range, and PiP does not.
If Toyota had room in the Prius to fit in a 16KW pack, then the Federal rebate would have been $7,500 (same as the Volt). If the cost of that additional ~12KW was $5,000 or so, it would be a no brainer... (the PiP already has a $2,500 Federal rebate). Most likely, a few things stopped them: The extra 12KW costs more than $5,000 more The extra weight would have affected the overal MPG in a negative way There isn't the physical space in the 3rd Generation under deck storage to fit 16KW In the next 4th generation 2015MY, if they do a major redesign, and battery density/pricing improves enough, it might be possible to get a larger pack in it...
Space was a major issue, there is no room. In the next Prius make no mistake it will be a larger battery, or denser...whatever allows, for added range.
I'm sure Toyota marketing is all over the whole "2013 PiP, now with 25% more range!" And they can pull that off for a few years. Not a difficult prediction.
Somehow, I really don't ever see Toyota making the of " 25% more range!" statement since that would cause potential buyers to realize how low the range still is compared to the Volt. If 11 EV miles isn't enough for someone, I very much doubt that 13.7 EV miles will make them reconsider.
Pointing out the consequences and advantages of having bigger vs. smaller battery pack is all good. Pros vs. Cons from different point of views (political, carbon footprint, energy efficiency, energy security, national pride, etc).