When using the <q> element for quotemarks there is a problem doing subquotes, "as in 'this is a' subquote."
Typically a subquote would be done like this: <q>as in <q>this is a</q> subquote.</q>
But WordPress, presumably wanting to close what it thinks are open tags, saves it like this: <q>as in </q><q>this is</q> a subquote.
So you end up with this: "as in ""this is" a subquote.
Instead of this: "as in 'this is a' subquote."