For people who want the burned in sub scenes clean, would it be possible to render just those scenes by themselves sans subtitles as an extra?

They could even be encoded at a slightly higher bit rate since they may be used in other projects and thus re-compressed later.

As a side note, I remember hearing about multi-angle and dynamic-branching back when DVD first came out. I've still never seen a really good implementation of it. Mostly the discs I have just stutter or hang when trying to use the feature. Fusion! Still only 50 years away!