Kurtenbach: January football is different. No team knows that better than the 49ers

There are two immutable truths that govern the NFL playoffs — unwritten rules that cut through the noise of EPA models and talking-head bluster.

Truth No. 1: In January, more games are lost than won.

Truth No. 2: When the margins are tight, trust the sideline with the better head coach and the quarterback.

Often, these truths independently operate. But on a windy Sunday night in Philadelphia, they intertwined in the 49ers’ 23-19 win over the Eagles.

While Nick Sirianni...