The Chiefs are waiting until very late in the play clock to show their hands and neither Hurts nor the line is handling them well. You might have seen me talking about Creepers and Stems.
Creeper means a defense in a base alignment sends a back 7 player and drops a down lineman. It's not a traditional blitz because the number of expected rushers doesn't change. Just their locations and angles. That means the QB and the OL both have to process that information well in a short amount of time.
Stems you'll also see called Stemming the Front, which describes what's happening much better. Essentially, it's a DL Shift. Sometime it's moving everyone over a Gap. Sometimes it's as signficant as moving from an Even to an Odd Front or vice versa.
These happen very late in clock and Spags is layering them fantastically. You'll see him using both on the same play. So the line may shift over a gap and then one of those guys ends up dropping while a DB blitzes like happened on the early Fumble. It's a lot to process.
