Last, but not least, you asked, “Wouldn’t the enclosure symbol be easier to understand when preceded by the shape termination symbol?”

I cannot say whether that would be easier to understand. However, I can point out that section 14.3 is titled “Combined shapes,” and its first paragraph says that physical enclosure takes two symbols and makes a new, previously undefined symbol. For example, the “circled plus” is a single entity with a meaning all its own that is distinct from the “plus” and the “circle.” So, the enclosed shape is part of the overall shape, and it would be inappropriate to put a shape terminator between the circle and whatever is enclosed.

I think the next necessary question is, “Does physical enclosure accurately transcribe the meaning of ‘circling’ in print (like “circle the correct answer”)? … Or would a typeform perhaps do a better job of transcribing the meaning of ‘circling’ while physical enclosure should be reserved for situations where the enclosing and enclosed shapes become something different from either (like the circled plus described above)? I do not have an answer to that question, and I suspect no one else does for sure either, for now.

Thank you for sharing your astute questions!

Please let us know if you need anything more or different.

–Kyle