In a series of grammatical attacks against the MLA, I have for some time (grader permitting) refused to put a punctuation mark that ends a quotation within the quotes. The one exception would be an isolated quotation, say, in the midst of some dialogue; since, in this case the sentence can be construed as the quotation itself. Otherwise a period at the end of a sentence but within a quote could only signify that that which was quoted has ended—but not that the sentence containing the quotation has ended. Hence we have grammatically correct sentences by my account:
X said “blahblah”; then Y laughed.
Z told me yesterday that “blahblah”.
Then there are those that would make any logical parser misinterpret:
X said “blahblah;” then Y laughed. (parser returns error: run-on sentence detected)
Z told me yesterday that “blahblah.” (error: sentence not ended).
Aesthetics is NOT justification for a grammatical rule.