There are many ways to interpret the constitution and the last class I took on taught all of them.

And like anyone should trust what John Yoo says about the constitution anyway.

A report by the Justice Department's Office of Professional Responsibility stated that John Yoo's justification of waterboarding and other "enhanced interrogation methods" constituted "intentional professional misconduct" and recommended that Yoo be referred to his state bar association for possible disciplinary proceedings.

"There really aren't "many ways" to interpret it."

There really are. And throughout our history the Supreme Court has switched between them depending on how they wished to interpret it to resolve a case brought before them.

Different classes word it slightly differently but here are two examples of seven ways the Supreme Court has interpreted the Constitution.

1)
Textualism
Originalism
Moral reasoning
Living constitutionalism
Strict constructionism
Pragmatism
National identity

2)
Historical Interpretation
Textual Interpretation
Structural Interpretation
Doctrinal Interpretation (precedents)
Prudential Interpretation
Traditional Interpretation
Moral Interpretation

And Yoo is an idiot who tried to justify cruel and unusual punishment because some humans aren't Americans and so that made it ok? No wonder many wanted to investigate and prosecute Yoo under various anti-torture and anti-war crimes statutes.