Texting in fifteenth-century polyphony causes editorial difficulty and resists analytic control because ambiguity within and variation between sources preclude the establishment of single alignments of syllables and note groups attributable to composers. Scholars have therefore been cautious in drawing general conclusions as to the principles which underlie texting at this period, and their relation to texting practices in earlier and later repertories.
One mid-century theoretical source attributes responsibility for texting to scribes, not composers. Scribes of most sacred sources in the first half of the century copy both text and music, a procedure which gives them complete control over the alignment of syllables and note-heads. Manuscript text placement therefore represents the scribe's sound-image of the music; this reflects both the texting in the scribe's exemplar (going back eventually to the composer) and the influence of individual scribal musicianship.
Individual scribes' texting preferences when copying liturgical settings and carols by Dunstaple, Dufay and others relate to word-divisions, verbal accentuation and melisma placement. Sensitivity to verbal accent also underlies the composers' syllabic rhythmicizations under certain circumstances; beyond this, composers control texting by prescribing large-scale distribution of syllabic and melismatic passages without necessarily assuming the replication of any one precise alignment in every performance or further copy.
A distinction between syllabic, isochronic and melismatic texting can therefore be seen to underlie texting at both compositional and scribal levels. Changing methods of writing texted music during the course of the century arise from the combination of these well-established principles with changing musical styles; the significance of the later period therefore lies more in new ways of thinking and writing about texting than in new compositional texting practices.