Is the harm that the average ethical review board prevents less than the harm that they cause by preventing research from happening? Are principles such as requiring informed consent from all research participants justifiable from an utilitarian perspective?
I'd think 'ethical' in review board has noting to do with ethics. It's more of PR-vary review board. Limiting science to status-quo-bordering questions doesn't seem most efficient, but a reasonable safety precaution. However, typical view of the board might be skewed from real estimates of safety. For example, genetic modification of humans is probably minimally disruptive biological research (compared, to, say, biological weapons), though it is considered controversial.