"I can't figure out what this paragraph means --..."

Even more surprisingly, when we have complex systems of "$A$ is true if $B$ is provable and $C$ is not provable" plus "$C$ is true if it's provable that the consistency of $\\mathcal T$ implies $B$ and $D$" etcetera, we can compute exactly what is and isn't provable in polynomial time\.

I can't figure out what this paragraph means -- I have no idea what the "et cetera" could be. I'm wondering if "when we have complex systems of…" should be "when we have complex systems such as…"