(I'm one of the Highlight.io founders). Yep, that's the intention. And anecdotally, it works pretty well, even without fine-tuning.

We started working on this before any of the fine-tuning APIs for OpenAI came out, but we are keeping an eye out for support for fine-tuning on more OSS models. I suspect it would result in better results, especially if it were trained on only exceptions, for example.