Re:The Punctuation Guide
by Stratoscope on Thursday September 28, 2017 @06:56AM
(#15356176)
That's an excellent point. Perhaps this is another case where it would be better to rewrite the sentence:
"Frankly, your work has been awful."
"Your work has been frankly awful" has frankly as an adverb. That is, it was awful in a frank way.
"Your work has been, frankly, awful" makes it clear that frankly is a parenthetical remark that isn't part of the sentence.
With commas 'frankly' modifies how the writer intends the sentence to be received. Without, it modifies how awful the writer things your work has been. I suppose in some situations, the absurdity of 'being awful in a frank way' is sufficient to resolve the ambiguity.