Optimal solution to develop a wordpress theme?

I like to do this as follows:

  1. Go to underscores.me, fill out the theme name, and download the theme.
  2. Strip out the parts of this (somewhat clean) template that don’t want to use.
  3. Start building your own template with the functionality that you wrote.

This way you will have a clean template to start with, and no core theme functionality provided by the theme you decided to use as a dummy.

I don’t know exactly if there is any “right” way to build your own theme, only that the Codex insist you use the WordPress Coding Standards, CSS Coding Standards and that you follow the design guidelines.
I think that, except of the parts of the Codex a developer is free in how to develop a theme.