I was pointing out that a spellcaster in such a campaign would not be a desirable PC choice, because what he or she could do would be done better by someone else.
Is that true though? The Shaman can walk on coals or through a blazing fire (Endure Elements), strike fear into the hearts of your enemies (Bane/Doom), speak to the spirit world and receive advice (Trance/Commune with Lesser Spirit), pacify the leopards guarding the imperial palace (Calm Animals), bless a weapon (Weapon Bless), and hide the party from pursuers (Obscuring Mist).
Given that there would be no other spellcasting classes to compete, it sounds like there's quite a bit even a low-level Shaman could do that no one could.
The main gist of what I'm saying is: if a class is so underpowered that it can't compete with the other classes, it won't be a popular choice with players, regardless of how well it captures the feel of legends or fairytales.
Is the existing Shaman then such a class?