The Patriots, with Hoyer and Stidham, almost beat the Chiefs last year.
Hoyer and Stidham both threw for a combined three interceptions, punctuated with some of the most god-awful foibles. Hoyer fumbled in the red zone. Hoyer took an unnecessary sack when he could've thrown an incompletion to go for a kick, which would've put us at 6-6 going into the half. Hoyer threw an int. Stidham throws an int after Hoyer gets benched. WR's couldn't get open. etc.,
This highlights a few things: even really weak teams have strengths that make it really hard to win (our defense kept the game competitive).
The Chiefs would need to enjoy a comedy of errors to win that game.
tl;dr - it's really, really, really difficult to go 5-0, let alone 20-0. although I'd be more surprised if he said "I'm a realistic guy, I expect a few losses" lmao