In an updated report, Consumer Reports has reversed course and after retesting the 2016 MacBook Pro now recommends Apple’s latest notebook lineup. The retesting was performed using a beta version of macOS Sierra, which fixes a Safari bug that caused the erratic battery life seen in the original round of tests.
With the updated software, the three MacBook Pros in our labs all performed well, with one model running 18.75 hours on a charge. We tested each model multiple times using the new software, following the same protocol we apply to hundreds of laptops every year.
The publication tested two 13-inch MacBook Pro models, one with Apple’s new Touch Bar, and one without, and a 15-inch model with a Touch Bar. (All of the 15-inch MacBook Pro models boast a Touch Bar.)
Now that we’ve factored in the new battery-life measurements, the laptops’ overall scores have risen, and all three machines now fall well within the recommended range in Consumer Reports ratings.
Average battery life results were as follows:
Consumer Reports purchased all three computers at retail, to ensure they are testing the same models a customer would buy. (This is a standard component of all Consumer Reports testing.)
Consumer Reports originally withheld their purchase recommendation in late December, due to an extreme variance in the battery life of the laptops during testing.
For instance, in a series of three consecutive tests, the 13-inch model with the Touch Bar ran for 16 hours in the first trial, 12.75 hours in the second, and just 3.75 hours in the third. The 13-inch model without the Touch Bar worked for 19.5 hours in one trial but only 4.5 hours in the next. And the numbers for the 15-inch laptop ranged from 18.5 down to 8 hours.
Apple worked with the publication to determine what caused the wildly varied battery life test results. The investigation led to the discovery of an obscure Safari caching bug. Consumer Reports had used a developer setting to turn off caching in Safari, which triggered an “obscure and intermittent bug reloading icons” that led to the inaccurate testing results.
Although the bug is not one the average user would likely ever encounter, as most users wouldn’t turn off Safari caching, Consumer Reports performs that step in all of its testing, in order to ensure a uniform testing environment.
The bug is fixed in macOS Sierra 10.12.3 beta 3, and the fix should be a part of the new OS version when it is released to the general public. (Beta four is the currently available version available to developers and members of the Apple Public Beta Testing Program.)