There is 0% doubt left that this mbp that people have waited 4 years for has worse battery life than the previous generation across the board. It's due to 1/3 smaller batteries in the 13" models and 25% smaller batteries in the 15" models. A more efficient screen and more efficient CPU is not able to make up the deficit. In fact, under load the battery life is even worse because the size of the gas tank is less. These laptops are sipping power only a little slower rate than 4 years ago, but apple put in an even tinier gas tank. So for sure the battery life is worse. There's no advanced degrees needed for this. The fact that everyone on this forum, mac lovers, who want to justify their investment, are universally reporting lower battery runtimes in both unrealistically easy and realistic usage scenarios, settles the issue.
The only issue is if you can live with it. I think people can live with it because in a year your battery life goes to mush anway. But what many people can't live with is the principle behind it....so expensive for so little, etc etc ad nauseum.
Apple will still sell alot of these, but not to as many of the core audience. Once the core audience gets wandering eyes, even though they are small in number....watch out. No one's on top forever. Imagine if Honda stopped focusing on the accord and started focusing on building a Benz competitor. Weird, huh? But that's exactly what apple's doing. Apple has this odd way of making things binary--it must be this way or we'd rather not build anything at all. As a company they overthink things. They think, "We must focus and build the one-true-computer" even though they have more money than any company in history. We can't target two markets at once. That's not what they say, but this is what they are showing by their actions. Also, oddly, everything they do from the even more outlandish focus on design, to the pricing. to the marketing budget to make up for the lack of innovation, to what they sponsor, to their alliances with the fashion industry, to the $300 coffee table book claiming they took 8 years to design special inks and linens all while ignoring of the airport routers and abandoning the display market, etc.....their behavior reminds me very much of a jewelry company now.
The most telling sign is that what takes the longest to build up--brand image--is starting to erode in the eyes of basically everyone. Once that happens it's kind of a done deal as the death spiral begins.