Asaki said:

I just don't understand how mixing it with BluRay footage would make it look better.

It's not entirely about looks (although the comments above about the Blu-ray being based on earlier-generation sources are true). Even if this thing gets released and it looks better than every other video source out there, it's very unlikely to be GOUT-synced, so alternate audio tracks, etc will not work out-of-the-box with it. Having someone GOUT-sync this video would be worth it, even if no other video sources were used.