Interestingly, this is the EXACT advice [1] given at the Apple + FBI @ U.S. Congressional Hearing on March 1st from California congressman Darrell Issa (R).
Congressman Issa was previously the CEO of DEI, a car security and audio equipment company. He is possibly one of the most tech-savvy members of U.S. Congress and happens to be one of the wealthiest as well [2].
The Congressional hearing video footage is here, the suggestion was proposed at 1h23m 13s in.[3]
I noticed the same thing. I wonder whether James Comey's aw-shucks answer (roughly, "I have no idea, I'm just a regular Joe, I don't know much about the tech here") was feigned.