No, Not Really

Said a co-worker the other day: "It's really a matter of deniable plausibility."

Deniable Plausibility?! That's wondrous:

Person 1: With utter certainty and without fear of contradiction I aver that this thesis is entirely plausible.
Person 2: No it's not!
Person 1: Dang, you're right.

Of course, I'm eminently professional, so I just offered a polite and muted correction.