From my experience, companies try to promote the introduction of foods at an earlier age because, in the words of an executive from one company, it stops parents 'drifting into home-prepared foods'. They make special concoctions to be fed by spoon and some parents are drawn into seeing it as a positive sign of development if their child takes to 'solids' at a younger age than its peers.
With baby-led weaning, babies can share in the family meals (with attention given to salt levels, of course). They develop a discerning palate. And while they may be behind the babies eating processed pap off a spoon, at 8, 9 months they are feeding themselves with a spoon and enjoying what they eat.
At least that is what you see in the films in Gill's presentation and there is plenty of supporting testimony on various discussion groups and boards.
This new book gives plenty of information on the theory and practice of baby-led weaning. It is well worth investigating. Available at: