Ripping by Index

[simbun]

Is there any way of having TrackNumber appear as 1, 2.1, 2.2, 3.1, 3.2, 4, etc?
I've tried the obvious (value.display= and .displayFormat=) but they don't seem to operate on TrackNumber, I assume this is a forced limitation?

It's for tracks that have multiple indexes such as the Buster soundtrack. I believe it's more common in Classical music, but I have a small number of CD's like it, and if I were to "rip by index" and number them separately I'd be able to access the songs directly, rather than "rip by track" and have to forward through the track to get to the next song.
If it were possible, I'd potentially split up some other tracks where a single track contains multiple songs.

I think ripping by index would probably cause automated tag scraping to fail, but it's easy enough to do it manually for the few that need it, and I can create a CUE to piece it all back together for verification purposes, so that's fine.

I know I could just change the title (using displayFormat) to include the '3.1' from another tag, but I'd really like to get it working "properly" if at all possible.