Another note: It's in the PHB2 that things start to get messy; the Invoker is a Chain-wearing Controller that uses the previously-only-for-warlocks rods and
not holy symbols, meaning that when trying to find an appropriate rod, one has to painstakingly look at each description to make sure it's actually for the class in question. At the same time, they're restrained from being able to use the implement whose effects are pretty much
guaranteed to work with divine classes.
The Druid did the something similar to hide as the Invoker did to rods, introducing several "while in beast form" enchantments that meant even if you were meant to wear hide, the enchantment would be functionally nonexistent.
And the Shaman introduced the possibility of a leader who wasn't expected to wear chain as the default (and the other build had to spend a feat to get it), creating a bunch of leather armors whose effects were nonexistent without a spirit companion, and, combined with Invoker getting chain, blurred that whole "chain is the assumed armor of leaders" thing that was going on. And so they added "when you use Channel Divinity" effects to chain, but that ruled out two of the divine classes (who would be in Cloth and Plate, respectively) from the ability and made the chain useless to the classes that would be accustomed to looking at enchanted chain.
(And, of course, Barbarian at-wills were mostly useless to Halflings and Gnomes.

)
I'm not sure if this was the right direction to go, overall. It seems like beast form enchantments and spirit companion enchantments would have been better served being on totems instead of armors, while Chain could have remained focused on leaders (given the Divine class leader subtheme, Invokers in chain wouldn't be out of place). The PHB1 was scrupulous in avoiding armors that referenced specific class features. The contrast between Rods and Orbs (Warlock-specific and WIzard-specific, respectively) in the PHB1 also speaks volumes, with Rods very directly referencing a class mechanic, while Orbs provided class-neutral benefits with a control theme. Wands were restricted to power source (Arcane).