Pattern in major scale chords

[Bob]

Misc. note.  If it helps anyone. 

I just notice today a pattern in major scale chords.

I ii iii IV V vi viio

There's a pairing of like-quality chords.

M m m M M m dim

or...
Major
minor minor, ii iii
Major Major, IV V
minor diminished, vi viio

If you look at the diminished as being nearly minor, the pattern continues.

[Petter]

What do you mean Bob?! I´m puzzled 

[Bob]

After I, it's groups of two similar quality chords.

I/Major   Then ii and iii are both minor.   IV and V are Major.  vi and (almost) viio are minor(or almost). 

Almost like you've got Major in the middle (IV and V) surrounded by minor.  (almost)

I Major       minor (ii and iii)    Major (IV, V)   minor (vi, viio)