David's songs could not be the height of certain MK classics in DS, yet he had songs that owed nothing to songs such as Angel of Mercy, Follow Me Home, Love Express, Les Boys. Songs like What's the matter baby in which the lyrics and melody is a partnership of siblings could be contained in either of the first two albums and could be the first of other siblings' partnership. Of course, as well as other bands like Beatles, Queen, Eagles, that other members could participate with one or more songs, it would not diminish the brilliance and importance the presence of at least a song from another member of the band in that period. (What's the matter baby, Bernadett, Sacred loving), the band was a unit, it worked that way, that's what I feel when I hear Sultans of Swing or What's the matter baby as well as Bernadett.
Now, of course, even some of Mark's songs did not come in (Eastbound Train, Me and my friends, Real Girl, In My Car), should have the producer's finger, at least live they played them.