Entering fractions in plain text is consistent with the very core of Unicodeʼs purpose, which (please check if Iʼm right) is to empower all people on earth to get in readable plain text as much information as possible. As fractions, that ISO wanted to stay called “vulgar”, are part of this information, the designer of Arial Unicode MS matched precomposed fractions, superscript and subscript digits and the fraction slash so that in the cases where equal precomposed fractions exist, [superscript digit(s)] U+2044 [subscript digit(s)] looks exactly like [precomposed fraction]. I really canʼt see any difference. If we look at the example in the demo files, we get convinced that in Arial Unicode MS, U+00B3 U+2044 U+2085 ³⁄₅ is congruent with U+2157 ⅗. DejaVu Sans and DejaVu Serif and their Condensed variants are some other fonts that work. Well, a lot of other fonts donʼt, because they are uncomplete or for some other reasons, but I cannot really infer from what I see on my machine, for the reason that my versions are uncomplete.
You may test it by yourself and you are still welcome to download the samples: .docx: http://bit.ly/1DNPtf0 .pdf: http://bit.ly/1JutBGK The lesson I learned from this is that proportionally spaced fonts which comply fully to the Standard, allow users to get nice fractions without formatting. Obviously that does not work with monospaced fonts, nor does it look nice when the ASCII superscripts (¹²³) and the other super- and subscripts are not of the same font, as it may occur in browsers but also in word processing. To run this—well, call it a trick, we must make sure to use a convenient font. But at this condition it works, and I see no reason not to do it. Even more, I do not consider it as a mere trick, but as normal usage. The problem weʼve now to deal with, is why this usage is hidden in the Standard. And Iʼd like to bring immediately my answer to the question, an answer inherent in what I wrote yesterday: The plain text custom fraction input method is not recommended in TUS *because* fraction formatting is a part of desktop publishing software but not of office automation software. That may be wrong, and I didnʼt check whether at one time of history, Unicode has removed plain text custom fractions from TUS, or not. Nor can I know whether Unicode has been urged to remove / not to inform, or not. However, a number of facts lead me to the supposition that software marketing reasons are implied. I need probably to underscore that Iʼm not here to disturb business, but to try to help to improve user experience, worktool usefulness, and overall productivity. Regards, Marcel