Medieval Manuscripts with Foldouts

[oshfdk]

I wonder how our perspective on the foldouts would change if it is true that the MS wasn't necessarily meant to be bound.

I think these are two separate questions: whether the manuscript was actually kept for a long time as separate leaves and whether the manuscript was designed to be bound eventually. While I find it quite possible that the manuscript was kept as a stack of bifolios (or whatever they are called) for many years, the fact that the gutter space free of any text or drawing is present on almost every bifolio with rare exceptions that could have been intended as centerfolds, to me is a very clear message that the creators at least thought about binding it into a book. While the creators were comfortable with writing over the folds like on f102 (if I remember correctly), they would never write on the gutter. If the manuscript was designed to be kept forever as separate leaves, there would have been no reason to keep the gutter empty, it would be just another fold.