I can only find one related to sub- and superscripts there: "2011-1 SUBSCRIPT SOLIDUS: Proposal to encode subscript solidus as a modifier letter."
Disposition: The UTC did not agree that the exemplified usage constituted plain text or required
encoding as a modifier letter. The fact that some commercial software modules can only handle
plain text is insufficient argument for claiming that any particular printed superscripted or subscripted
character must be encoded as a separate character. The soldius is already encoded. The character
in question is simply a solidus shown in a subscripted expression, which can be represented via
markup or styling. References to UTC Minutes: [126-C8], February 8, 2011.
This was 5 years ago, and they have revised decisions in the past (search that page for "revised"). The decision is not marked as "Precedence", so does not seem to require a special majority to reverse.
The official dispositions of past proposals that were formally not approved seem to be here:
http://www.unicode.org/alloc/nonapprovals.html
I can only find one related to sub- and superscripts there: "2011-1 SUBSCRIPT SOLIDUS: Proposal to encode subscript solidus as a modifier letter."
This was 5 years ago, and they have revised decisions in the past (search that page for "revised"). The decision is not marked as "Precedence", so does not seem to require a special majority to reverse.