Is Waterboarding A Red Herring?

Unsurprisingly, President Bush vetoed a bill that would have limited the CIA to interrogation techniques listed in the Army Field Manual. Everyone's assuming this is to permit continued waterboarding. I don't think so, particularly once I heard John McCain was on his side. I bet it's more about permitting derivations of the Active Denial System to be used as a real-life version of the gom jabbar.