Would you mind to elaborate a bit more? Seems to be very interesting fact.
Picture a piece for 3 players -- 2 soprano instruments and Basso Continuo (a bass instrument + let's say, harpsichord). It's a piece with a recurring harmonic structure; say, Passamezzo or ciacona -- think Pachelbel Canon.
The BC in this particular instance might only have barlines every 8 measures. The soprano parts might have barlines every 8 measures too, but might also have them where a significant change to their melodies change. Like, when a flurry of 16th notes begin to crop up.
Now, this isn't always the case -- it's definitely inconsistent, but such things show up enough that those hints cannot be discounted at all, and seem to be enough of a performance hint to at least be noted and appreciated by the performer.
Re:Notation as a Tool of Thought (1979)
by tnecniv on Saturday December 17, 2016 @05:59PM
(#13203228)
Was bar placement not standardized to be at the end of every measure?
No, bars were not standardised at all!
One could interpret placement of barlines as something close to paragraph markers -- not all the time, but often enough that they seem to indicate specific intent.
Where the manuscript writer (or print publisher) chose to put bar lines, for instance, can give clues as to intent in performance. I'm thinking specifically about Venetian publishers in the 17th century -- but there are plenty of other examples.
Notation can be incredibly important when trying to discern intent in some disciplines.