How do you allow certain users to have permissions for certain nodes

A view posted this question to me, and I wanted to go ahead and share the question and response:

... More specifically, I got to the point where I wanted to assign an editor/teacher to work exclusively on a node yet retain the author/student information as it was. The revisioning modules provide for doing this in terms of types of users so I could say - "All teachers can edit this node" but I could not say "This one teacher can edit this node" To me this seems like quite an obvious function that could be applied in many more areas than just the student/teacher scenario. Anyway so I've finally concluded I do need to code to provide basic if not slightly customized functionality. I felt I could have saved time if Drupal has not oversold what was possible without code but there you go. Do you have lessons that might help me with this king of thing? I would also be interested in your opinion as to the advantages of drupal over other API's or CMS's. I am impressed with the ease in which I can create content types and content and users and permissions etc.

And my answer:

Hi there,

Great thoughts, thank you for taking the time to send them my way. For your specific requirements, where you need to allow only a particular user to user a particular node, you should be able to use http://drupal.org/project/content_access without any real bending. Let me know if that works. I have a few videos on access control, for example https://buildamodule.com/video/drupal-7-core-concepts-how-to-work-with-n... and https://buildamodule.com/video/drupal-7-core-concepts-how-to-work-with-n... (both subscriber-only), These are concept-driven and specifically geared towards folks trying to understand what's going on behind the scenes with access control and can give you an idea of how access-control modules work.

As far as comparing Drupal to other CMS's or platforms, I'm limited in what I can say simply because I have much more familiarity with Drupal and have some bias :) . The fact that a lot of really big projects are moving over to Drupal says a lot about this, though. Drupal has enough power and flexibility to be used at a scale that I've never had to deal with on my own projects. What you described with a kind of 'false advertising' around the flexibility of Drupal is probably more of an effect of the steep learning curve associated with it. There's a good number of new concepts as you come from another platform or programming language, and and lot of ground to cover if you want to know what's available even in core Drupal, much more so with contributed modules. The only shortcuts there involve doing what you just did, which is to ask other people what they think, and if they've heard of a tool that can do something in particular. There's almost always an answer in Drupal, and if there's not, there's at least other people who have some thoughts on it to get you started.

Thanks again, and let me know if there's anything else I can do to help,
Chris