I guess so, but changing 'set to 'assign would seem to indicate some sensitivity about the internal details on the language designer's part, and I think they are more important in code-as-spec languages like Arc. Granted you're right the naming of 'scar etc. isn't as important as the naming of commonly used forms like '=.
I believe set was renamed to assign to free up the name for a better use.
The way I think about it: code as spec implies the implementation should be concise and easy to read, and externally exposed names should be approximately hamming encoded. Internal names can be longer without compromising conciseness (which is measured in tokens) or readability.
It's not black and white, just relative priorities.
