Harmy said:

Not really, because putting that matte around the subs took about 5 minutes, rotoscoping a new background into numerous shots from a low quality source, just to make something that is already there more visible and which would take hours, perhaps days for each shot is a whole different league. If I did that, why not go through the films and rotoscope out all the crushed blacks as well? Because it would take ten years, that's why ;-)

Harmy, I have actually achieved this to some degree using the same method I used for correcting the highlight clipping in Star Wars. It involves keying the crushed area within each colour channel and replacing it with the brighter of either (or both) of the other two channels. It's a little more complicated than that but that's the basics of it. Because it's a selective process you just need to pick a few of the worst affected frames and adjust for those.