I can all but guarantee McDermott and the coaching staff reminded the team of their beatdown they suffered last season at the Titans hands and the circumstances surrounding that game. If he didn't, he's foolish and McDermott is no fool. He's a wrestler and wrestler's never forget a beatdown and the motivation to pay that back in spades.
When a guy is THAT wide open 50 plus yards down the field, the last thing you want to see is an overthrow.
Allen, despite what some here think, made the absolute proper, safe throw to secure an absolutely huge gain.