I don't know, but I can only assume 2-3% is well within established acceptable variances for any product with a battery. On a ten hour battery, a 3% reduction is 18 minutes. Real world usage variances could easily obscure any differences--ones that would only be seen with two side-by-side phones with different chips. In other words, even that much of a difference is meaningless in the real world.
10/8/15 at 5:07pm