I think the Pzev has partial to do with it, or totally but indirectly. The warm up might hurt a little, but that's not hardly even calc amount. Your taking a min or two of idling. That will not even be enough to measure. I think the issue in winter is fuel blend period. The aero argument with cold air is rubbish. Anyone whom grew up around racing will know what in talking about. My cummins turbo truck with 600 HP is very very noticeable with winter fuels and additive for anti gel. It takes much more fuel. I think the restrictive exhaust kills this poor motor. Id like to read cylinder ex pressures on this. I'd bet it would be mind boggling the amount of back pressure there is. I also think the tuning for engine and CVT could be optimized for much better results in both milage and mpg's.
The AWD does factor in if your basing your arguments in milage vs a fwd car. I believe that's why every test I've read including CR, states the milage is great for an awd car. You take ANY other manufacturer that makes the same car in a 2wd and awd version and compare milage between them. It's very notable the difference between them. Even a 4wd truck or SUV will get better than an awd vehicle. So its a monumental accomplishment for Subaru to have an awd even over the 30 mpg rating. If your comparing classes of cars, i.e. subcompact hatch etc then it'll be class based and not drivetrain based, and this is mainly due to the fact that there are not many manufacturers building a comparable car to Subaru with awd etc. so it has to be rated in a class somewhere. I think everyone has accurate points in their arguments, however then they get a little misplaced. I think Zeeper has valid points as well, and in no place I read did it say you can't have opinions on something you don't have. I've read post after post with figures that were derived from averages and means. I'm sure there are fairly accurate percentages stating the differential in mpg with 5 sp vs cvt. so he can calculate it from his 5 sp just as anyone else can calculate from studies and tests from people you can only assume are competent. I mean, there are milages listed from vehicles you guys do not have, and prob never driven. Yet, you feel you have the right to comment on them. That's no different from having a like car, less different tranny. Most everybody whom posted were right at some point in their posts, and some were even saying the same thing, just using opposing tone. I think we will see much more of this type of deviations in vehicles as the mandates by the EPA to meet certain requirements ramp up. We are used to seeing more linear tuning, not there will be major tuning games to fly past these requirements by auto companies I'm afraid. It's all just a little silly to me. It's entirely possible to get mpg with power too, look at the corvette. The problem is the mindset isn't geared to that type of mpg, its geared to pleasantville where we all drive micros the same color in zombie fashion.