> Do you know other projects which dump the full help into stdout 
> when asking for the "full help"?

`ps --help` lists sections "<simple|list|output|threads|misc|all>". The "--help all" output is all sections, but truly all help is only available via `man ps`.

> For me, the best CLI is "git help", "git help init", etc. "git help 
> init" opens "man git-init". I don't know its behaviour on platforms 
> without manpage support, like Windows.

With Git for Windows, `git help <command>` opens an HTML formatted manual page in a web browser. It should use a new tab in an existing browser window.