As someone who made best progress following the ideas described in Starting Strength after trying numerous approaches that didn't really work, I'd say you can s

As someone who made best progress following the ideas described in Starting Strength after trying numerous approaches that didn't really work, I'd say you can safely assume N=2 now. Really, this book teaches a very "old-school" approach to fitness but as a matter of fact, it does work and it did indeed work for thousands and thousands of people already. I know we like to get all scientific on everything these days, and I think this is a good thing, but there's something about fitness and especially building muscle that makes intuitive sense without any science whatsoever: If you want to be strong, start lifting heavy things. Do that in a controlled fashion, with a simple workout plan, and you'll eventually succeed.