As an answer to this post: http://www.notat.io/viewtopic.php?f=2&t=42&p=639#p639
On the score you're talking about, I was just following the composer's indications (Dyens).John Ruggero wrote:[...] It would not be common practice now to put the fingering on the staff in a keyboard solo. The numbers would be placed above or below the staff in the white spaces. All publishers adhere to this principle, because numbers obscure reading. Only in special circumstances is this not followed, for example, to specify the inner note of a chord, or if the polyphony is very complex. I just looked through editions of Bach by Henle and Wiener Urtext, Haydn by Universal etc. and had trouble finding finger numbers not placed as I describe, even for chords.
I was inquiring because I do not know the guitar tradition and wondered. But even if there is more of this in the guitar literature—which seems likely, given the nature of the instrument—I don't understand why it would be used for a single line as in your example.
Anyway, as a guitar player, I've always put my fingerings "in" the score, or let say partially "in".
Here's the beginning of an original edition of a Sor' study (ca.1820):
Nowadays, nearly 200 years later, most of the publishers follow the same rules (right hand (i, m, a, x) on top and p below, left fingering left-top for the upper voice, left-down for the lower voice and ca.left for the middle voices):
And so do I.