Critical band members

Do you ever notice how switching a certain band member out ends up chaning your view of a band.

Example: Our Lady Peace lost Mike Turner and got Stephen Mazaur as guitarist. While the band had replaced it's bassist after their first album, I don't hear the profound difference like when they lost Turner.

Another scenario is Third Eye Blind. A pretty popular band in the 1990's, they lost their lead guitarist and seemed to have dropped off the map.

A slightly different scenario involves Creed and Alter Bridge. Creed dissolved, but the band (sans singer Scott Stapp) reformed with a new singer. The band, so far, as seemed to do well, and nobody gives a crap about Stapp.

Guns n Roses dissolved, yet Slash and Duff have seemed to go on alright with Velvet Revolver. Meanwhile Axl has become a joke more than a rock icon or legend.