Capn Bloggs
Doctor, VNAV (in any form) reduces the potential for crews to get vertically lost on the approach, esp those @#$%^ GPS NPAs that have a waypoint in the guts of the critical portion.
Follow the VNAV and monitor it as opposed to working it out yourself. Trust me. VNAV is goooood.
Precisely, and until all GPS approaches (most particularly those with a waypoint half way down the approach) have VNAV then more LHR type accidents are only a matter of time.
Baro VNAV isn't available for everyone. WAAS solves the VNAV issues nice and simply for everyone.
As for Galileo, how long has it been coming for now? It wouldn't surprise me if it never saw the light of day.