Combat is supposedly going to be tough enough even WITHOUT spells misfiring. A misfiring chance would make people shun the magic system Larian has crafted - if magic is going to be unreliable, then people won't rely on it.
Hmm, I'd still love to see some unreliability and surprise to magic, and perhaps what you say is true if it only applies to magic-users, so I'll have to come clean and confess that I love the concept of fumble in combat too - critical failures making swings and stabs go haywire. I don't find that frustrating, nor do I get some slapstick comic relief out of it, it just makes for great roleplaying, and D:OS is built around the concept of that - coop play would be a blast if fumble and fizzle are in.
