EDIT: CLARIFIED THE QUESTION
Is the circle of fifths also listing the relative dissonance/consonance of notes in a major scale? and not just a list of key signatures?
Consider the solfege ... a method of naming pitches where you can name the notes with their respective 'voice' instead of their letter name... for example the notes of a C major scale such as C-D-E-F-G-A-B-C can be respectively named do-re-mi-fa-so-la-ti-do.
C--D--E--F--G--A--B--C do-re-mi-fa-so-la-ti-do
But notice that the names for C and G are do and so, which rhyme.
This would seem to indicate that G actually sounds closer to C than any other of those major scale notes.
That is, the interval of C to G, a fifth, would be the least dissonant (most consonant).
This would also seem to be the reason keys are built on fifths - because if you're describing some system of values one would want to describe incrementally.
In other words if you wanted to give me a list of all digits you'd give me 0,1,2,3 etc. to show me how the system increments instead of some random list such as 4,9,6,1 etc. If you wanted to show me a collection of all possible colors you'd show me a rainbow spectrum color wheel kind of a picture instead of a picture of random color swatches.
And this is what Leonard Bernstein seems to be implying in this video ... see 3:00 minutes in where he reinforces the importance of the tonic-dominant relationship (I to V).
So all that said doesn't it follow that if C to G is the least dissonant interval that the following, least dissonant interval, would be a fifth of the fifth? ... C to D ... just as keys are built ... and so on?
C - G (C to G is least dissonant)
C - G - D
C - G - D - A
C - G - D - A - E
C - G - D - A - E - B (C to B is most dissonant)
After the B must come F# because, as you might see, every two notes (two fifths) the letter name increases by a whole interval.
C - G ... one fifth C - G - D ... two fifths ... C changes to D
... and two fifths up from D you get E.
C - G - D - A
C - G - D - A - E
That means two fifths up from E you get F# - not F (a half-step).
C - G - D - A - E - B - F#
And this must mean that F belongs on the other side, down a fifth from C.
F - C - G - D - A - E - B
... and this should be a list of dissonance and consonance ... ... *within the tonal system called 'equal temperament' where the musical building block is a half-step ... WWHWWWWH for a major scale ... each W whole is two H halves.
If we number the notes in the key of C from 1 to 7 ...
1-2-3-4-5-6-7
C-D-E-F-G-A-B
... then ...
F - C - G - D - A - E - B
... becomes ...
F - C - G - D - A - E - B
4 - 1 - 5 - 2 - 6 - 3 - 7
If you built the base chords (three notes, every other note) for each of these tones you'd get:
F ... F-A-C ... F to A is WW, A to C is WH ... recipe for Major chord, F Major
C ... C-E-G ... recipe for C Major chord
G ... G-B-D ... recipe for G Major chord
D ... D-F-A ... D to F is WH, F to A is WW ... recipe for minor chord, Dminor
A ... A-C-E ... recipe for A minor chord
E ... E-G-B ... recipe for E minor chord
B ... B-D-F ... B to D is HH, D to F is HH ... recipe for diminished chord, B° (B diminished ... diminished being 'reduced').
So now you can see the first three chords are major, the next three are minor and the last is diminished ... building chords from the fifths also establishes the dissonance of the chords ... harmony.
The first three are major chords ... the 4-1-5 ... the three most common chords of pop-music, the most commercial and most consonant.
The second three are 1-5-2 ... the three most common chords of jazz-music ... a little less consonant, a little more abstract and less commercial appeal.
So, to conclude, is it fair to say the circle of fifths is really also listing the relative dissonance/consonance of the notes of a major scale?
EDIT: ADDENDUM
What I'm claiming is that the interval C to G, a fifth, is the most consonant (least dissonant). Therefore another fifth would denote the note that is the next most consonant.
C-G Most consonant (least dissonant) (a fifth)(5)
C-(G)-D next most consonant ... After C to G, C to D is the most consonant ... the second note (2).
The third most consonant interval would be a fifth up from D, etc.
The result is 4-1-5-2-6-3-7 ... more consonant to the left and more dissonant to the right. Relative to the 1 the 5 is less consonant. Relative to the 1 the D is the next, less, consonant.
If the key was G, G would then be the 1, the D would be the next most consonant, then the A.
And as I noted above you can see the three most consonant chords to the I (the C chord, major, built from the "1" note) are I, IV, V.
The very next set of three digit is 1,2,5 which become the I-II-V chord ... which I'm told by thousands of videos on YouTube, is the core progression of Jazz (and would be more dissonant than the I,IV,V as it's