On your interesting point: I think that success in design pre-supposes that individuals are qualified to do the work. There are issues with relying on that, however.

Firstly, what do you mean by “qualified” ? Is there a university degree? A “long history of similar work?” It is not clear to me that (in security) there is much that one can tie down here, as most people who we might agree as qualified have done lots of stuff … some good and some bad. So I guess what I am saying is that “qualified” implies success which implies qualified which … makes it circular?

Secondly, we have an economic argument. What happens if the individuals fail to achieve? What have we lost? Their time, the company’s time, etc. In comparison, if the committee fails, then we’ve lost all their time, and it’s generally more people for more time.

So “better” might come down to simply showing that the single designer has a better chance of succeeding, in shorter time, than a committee. In which case we are Pareto-better-off, as the single designer will always be cheaper on success *and* failure. (OK, that assumes that the successes are equal. Back to the drawing board…)