Assuming the Mac battery reporting is accurate, even running tests at different charge levels, seems specious to me. In my experience, it doesn’t tend to be. I

Assuming the Mac battery reporting is accurate, even running tests at different charge levels, seems specious to me. In my experience, it doesn’t tend to be. I don’t think it’d be biased to one browser over another in that way, but I don’t for a second believe that it can be used to make a statement like “Chrome used 17% of my battery life over 3 hours, then Safari used 18%.” I think it would be much more interesting to put together ~40 hours worth of testing similar to what the author did, then run it with Safari until the battery dies, charge the machine for X hours (where X is the amount of time the battery takes to report 100% plus some margin) then run it with Chrome until the battery dies. Repeat as many times as you think necessary. That would take battery percentage remaining reporting out of any load bearing place, which I believe is absolutely necessary here.