Some quite prominent ragtime pianists do actually swing certain rags, of course, meaning to play them in triplet rhythm. Max Morath does it with Paragon and Maple Leaf, if my memory serves me correctly. One of James Scott's, Dixie Dimples, is written as swing and Troubador Rag also has a written swing strain. Then you have the seemingly age old debate about whether to use 12/8 or similar or assume the dotted note convention. I always write my own ragtime exactly as played, with tied 12/8 if it's swung. To do otherwise courts thorough confusion.
Many of the rhythms, particularly in contemporary ragtime, are neither one thing nor the other as played. This makes for a delightful state of affairs with several writers putting instructions such as "Medium Bucktime" (Frank French's Bucktown Buck) and "Tempo di Post Oak" (David Roberts' Washington County Breakdown). Precisely how the unititiated are to fathom these nebulous descriptions is not indicated. Roberts even goes to the extent of explaining in copious notes that certain groups are "mid-way between one rhythm and another". Brubeck sometimes writes out as played and sometimes doesn't. Thankfully, with him we have more recordings to go by.
As virtually all of Morton is swung, Dapogny instigates yet another convention in his transcriptions - that two successive ordinary quavers are to be played as swing. Very nice as long as other rhythmic complexities do not occur over the top of the metre. So, in addition to the correct notation, regrettably not used very often, there occur two incorrect ones in many transcriptions. If certain sections are straight (not swung) in the middle of these latter scores (e.g. the end of London Blues and quite a few places in Waller) they have to put the words "straight" or "regular" onto the printed page.
My own opinion is that all music is best written out in the nearest correct approximation, even if it means messy looking scores - but I'm probably in a minority.
Topic: Non-Classical Music?