I'm not dismissing it, I'm saying it's never been the bottleneck. Like you said, the feedback loop is A bottleneck, so is figuring out all the nasty things that nobody on HN seems to have heard of before, like "what are the requirements", "which tradeoffs can we make to get this done in time", "what is the architecture for this", and building it in such a way that you can guarantee that it won't fall apart in 20 years when your requirements change.