This is what I'm saying, this is what happened to us with our 6. They don't care if it's half as fast with degraded battery if their capacity results don't jibe with our experience (or test results). I won't be so paranoid as to say the fudged the results, and let the readers judge for themselves.
There’s hundreds of authorized Apple iPhone repair centers around just go and pay 80 bucks and get a new battery. The time is spent posting on the site you could’ve had it done!