To give you a faint idea of how meaningless battery benchmarks are vis-à-vis real life usage, here are results from Phone Arena - http://www.phonearena.com/news/All-bow-to-the-new-endurance-... - 9+ hrs for Xperia Z3 and 6+ for iPhone 6+ which is lesser than the S5.
"We measure battery life by running a custom web-script, designed to replicate the power consumption of typical real-life usage"
In other words I would be very surprised if any of these benchmarks translate to anything close to the numbers they proclaim.
Well they are both web browsing battery life benchmarks. If loading different web pages shows 5+ hours of discrepancy then yes from a user standpoint they are precisely meaningless.
No, it might mean that one of the benchmarks is meaningful and the other is not. Or it might be that they test different scenarios and could be useful to different groups of users.
What the discrepancy tells you is that there's something odd about the benchmarks that could stand to be better investigated/explained.
Ok, but they're not the same thing. Odd might just mean a different set of underlying assumptions that cause the numbers to misalign, or perhaps a bug.
"We measure battery life by running a custom web-script, designed to replicate the power consumption of typical real-life usage"
In other words I would be very surprised if any of these benchmarks translate to anything close to the numbers they proclaim.