What is the point of the notation of say a whole note in the lowest voice with the alto voice using that same note in piano music? The piano can't double the note.
Basically in almost any piece of music by the masters, you find melodic lines that notationally use the same note which can't be played by the instrument.
e.g., C in the alto voice and C in the bass voice at the same time. Sometimes I see them do this melodically: first note is in C in bass and second note, starting later but overlapping with the first, in the alto.
Of course, it makes sense when each voice is is from a different instrument.
Basically, for piano, the composer could have notated it using one voice and a rest in the other in the case of a harmonic unison and it would still sound exact the same(or is there some interpretation for this?)?
So did Bach in his Well-Tempered Clavier do this because he wanted to make the individuals lines clear and not obscure what was going on? Did he do it in hopes that it would be played by other things than the piano(a quartet for the fugues)? or what?
E.g., you can find examples in in bar 9, 21, 24 in the fugue 1 in C. Each case is different.