primitives is already a Ruby string, and reading/writing it will not be much of complex C code;
it will allow advanced techniques like "remove unnecessary primitive", or "rescale all/some primitives to another sizes" and so on;
I can't see any Really Bad Consequences in idea: I assume (though, need check) ImageMagick will just raise some kind of error on malformed primitves string, which can be just converted to Ruby exception.
I can't think of a useful use case for supporting this.
Editing primitives directly requires familiarity with ImageMagick, so I think it is tough to use.
It's a bit unholy idea, but...
primitives
is already a Ruby string, and reading/writing it will not be much of complex C code;WDYT?