I agree with the intention behind this, which is aimed at nailing people viewing CP, but I also agree that there are a ton of issues, such as shady sites with popups that could put CP images in your browser cache, or viruses, or porn spam, or other things where someone could, totally innocently, end up with CP on their machine.

It's a tough call. I would guess that in part the ruling (and the law underlying it) is to prevent pedophiles from coming up with bogus excuses to get off the hook, but I don't think that sacrificing the liberties of innocent people is worth it.