Quote Originally Posted by DJZen
Shields don't add to your defense. Having a shield means you have the chance of being able to block an attack. They also add to evasion, and subtract from Intelligence and Spirit. At least, they did in the FC version.
I remembered the purpose of shields some time after my post, but depending on how valuable one considers the Evasion stat, that info could actually strengthen my argument.

Personally, I don't disregard Evasion entirely, but I only bother with it if the stat can be raised to a high level relatively easily. Otherwise, I'd rather take consistent damage with a high defense to support me, than hope for an attack to miss altogether (but that's an entirely different topic).