In the key of C major, take the following progression:
C----Em----A----G7----C
I------iii------VI----V7-----I
In this progression, can the VI chord be analyzed as a borrowed chord from the major mode (parallel major) of the relative minor?
I arrived at this interpretation because:
1) The chord has no leading tone to G7, so can't be a dominant leading chromatic chord.
2) The preceding chord (iii) isn't the secondary dominant of the chord (V7/VI), nor does it tonicize it, so I don't see how it can be transient modulation or tonicization.
3) It isn't a full-blown modulation as it doesn't last long enough, no other chords from the key are heard, and no other notes from the would be key are heard, most notably the leading tone (G#).
The background to this is that I was listening to David Bowie's 'Space Oddity' (in C major). The A major chord during the middle eight guitar solo part (which I believe is a direct transient modulation) got me curious as to the above question.