Comment Re:Wh, not W (Score 1) 46
The useful battery capacity that the owner can get is complicated by the fact that these days batteries are rarely used directly, but rather their output voltage is adjusted via a step up or down converter, often more than once. You can see that with USB power banks, where the actual performance you will get depends on what voltage your phone wants, how much current it pulls, the starting and ending SoC etc.
A single number will never give you a good indication of performance, or even allow for fair comparisons. At least not at the consumer level, obviously engineers who understand all this still need that data.