I always found it a bit annoying that you could hear Stevie better on Walter Egan and John Stewart albums, than you could on some of the Fleetwood Mac albums, but I think Justin (Sorcerer386) might be onto something.
Given that Lindsey was the lone male "voice" in Fleetwood Mac (in so much as Mick and John don't sing on record), perhaps it was a conscious decision by him, or even the entire band, that many of his songs wouldn't feature backing vocals from Christine or Stevie, but that their songs would typically feature backing vocals from him.
So as to have more of the masculine to balance the feminine.
Seems as plausible of a possibility as any.
