I wonder how good a job the ClearScan feature on Adobe Acrobat would do. IIRC it creates one or more fonts based the existing characters in the PDF. So each lowercase 'a' would look the same, and be a sort of average of all the 'a' letters in the book.
Interesting – I have some old British academic press books with "advanced" typographical features; I'll see how it does with them. (The type you have to break out advanced typography features in Adobe apps to set – old style and modern numerals, interpuncts, two types of ampersands - one for headings and body text, swash alternate forms in titles.)
