Yes, but “The Defense Professor” and “anyone else who can rig the wards” shouldn’t have the same probability in his mind. What with all the rest of Quirrell’s strange behavior and the curse on the position, “The Defense Professor” should be allotted a massive probability, with a comparatively smaller piece left for “whoever else has the ability to do this.” He should be suspect number one by far.
Yes, but “The Defense Professor” and “anyone else who can rig the wards” shouldn’t have the same probability in his mind. What with all the rest of Quirrell’s strange behavior and the curse on the position, “The Defense Professor” should be allotted a massive probability, with a comparatively smaller piece left for “whoever else has the ability to do this.” He should be suspect number one by far.
For that, I’d point to undermind’s comment that this is only what Harry wants the Malfoys to know.
There might also be an element of Harry’s art as a rationalist being forgotten when he needs it most.