Yep, in most situations it is my preference to read directly from the manuscripts. I specialize in the 13 course Baroque lute and overall we are used to reading handwritten tablature as this was the primary notation for this instrument which predates the widespread adoption of modern notation. Because of the rarity of our instrument and its notation, it is often the case that there are no modern editions available at all, and even if there are, I tend to not trust the judgement of the editor and prefer to work from the original manuscripts. Because of the fact that the 13 course lute disappeared into more or less complete obscurity after around ~1785, we have been without a robust academic infrastructure to support scholarly research about the instrument for quite a long time- in fact until around the late 20th century, so even with a modern edition, I would venture to say that it would be irresponsible to play solely from it without at least checking the original source.

What is great is that nowadays with an iPad Pro, and Apple pencil, we have an ideal situation to read directly from original manuscripts in full color and in high fidelity. It is especially helpful to have all of the manuscripts in your library and to be able to compare different concordant versions of the same pieces from different manuscripts.

Regarding legibility, yes there are issues. For example, in the Dresden manuscripts, D-Dl Mus. 2841-V-1,1-6, which contain possibly the greatest collection of music by the most prolific composer in the history of the instrument, Sylvius Leopold Weiss (1687-1750), there is major water damage incurred on many pages as a result of the firebombing of Dresden in 1945 at the end of WWII. With the iPad, the Apple pencil, and the high quality scan from *SLUB, it is possible to draw on a layer directly on top of the manuscript in the ForScore app, and make it legible.

I think there is something to be said for performing directly from the original manuscripts, and in the case of Sylvius Weiss, often from his own handwriting. I personally take comfort in the fact that there is nothing between my interpretation and what the composer left us. There is also a spiritual aspect to the practice of reading from primary sources. I find it somewhat magical to make music directly from the same score that the composer or scribe was using and was left to us.

And because the lute is rather "new" as in very few people are familiar with it, reading through these sources is a bit like being a musical archaeologist. There are so many treasures to be found and aspects of music making that we as modern society have forgotten or are oblivious to. These treasures are sitting in manuscripts of early music across the world, waiting to be found. It is so important to understand just how they made music in the early history of humanity where there was no television, phone, no recorded sound and so forth. There wasn't even an international pitch standard! Studying each stroke of the quill in these manuscripts helps us give insight into their musical and artistic intentions. I believe it leads to better music making, at least for me...

*SLUB = Staats- und Universitätsbibliothek Dresden, Sächsische Landesbibliothek

*Here is sample of one of the good pages from the Dresden MS, Sonata 38 by Weiss: https://ibb.co/72PbHPc

*Here is a firebombed/water damaged page: https://ibb.co/RHsgjS4