Can I ask a serious question. What task are you writing where its ok to get 7% error rate. I can't get my head around how this can be used.
Historically speaking, if you had a 15% word error rate in speech recognition, it would generally be considered useful. 7% would be performing well, and <5% would be near the top of the market.
Typically, your error rate just needs to be below the usefulness threshold and in many cases the cost of errors is pretty small.
That's very different from just knowing the aggregate error rate.
Humans make a ton of errors as well. I didn't even notice how many I was making here until I started counting it. AI is super useful to just write get a first draft out, not for the final work.