Code Reviews Considered Hurtful, why?
First, read this link from extreme programming website: http://www.extremeprogramming.org/stories/pair7.html
The same principle applies to any project artifact review, whatever it is requirements document, design document or plans. What is we should stress is collaboration on the artifacts with all involved people and all people who could give feedback per their role or experience in the project or similar projects. I wonder why we should replace collaboration with criticism which will lead to non objectivity in most cases.
Per the Agile Manifisto, where people and interactions are given more value over processes, stick to value people and collaboration over criticism. Detect any problems early while creating the artifact other than delay it to review after its creation. By doing so, you will foster a collaboration environment other than a bureaucratic process followers.