> The source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable. However, as a special exception, the source code distributed need not include anything that is normally distributed (in either source or binary form) with the major components (compiler, kernel, and so on) of the operating system on which the executable runs, unless that component itself accompanies the executable.
They (more than likely) are python scripts so the install step is copying to the addon folder.
Haven't looked into the blender thing in a while but someone could use the generated C++ API to create an addon and make it difficult to install but who knows if anyone (other than cycles) uses it.
I don't really support it, but this exact method appears to be working pretty well for Ardour (and yes, they are using GPL 2). It has resulted in some awkward situations, such as Ardour being available in the package managers of some Linux distros, but only as outdated, poorly installed versions. I remember installing such a version and finding it basically unusable.
Nonetheless, this technique gets them patrons, currently at 3701 subscribers giving $8819.00/month.
Last I checked, Ardour was fairly easy to install from a git checkout, at least on Linux. Their website advises uses to install the paid binary instead, but in practice it's easier to install from source than Blender IME.
>The source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable.
Worded a bit differently in v3
>The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities.
Then only the most motivated users could get it for "free"?