There are many paid and free Drupal training sites on the internet. To the best of my knowledge, none of them is open source. And I'm quite certain none of them is "ridiculously open."
I was having trouble getting a feature to enable correctly. It wasn't creating all the fields for the content type it defined. It built some of the fields but not others.
I was writing an extremely simple custom module (for a D6 site) to make use of hook_block. Every time I enabled the module the blocks no longer displayed on the pages.