McCarthy won't have his job in jeopardy but a loss against Dallas will be his fourth home playoff loss (and third for Rodgers).
That's a high number and I've noted on here I consider a home playoff loss a "cardinal sin" when assessing the career of a head coach or a quarterback.
Look at the three home playoff losses - 2007 NFC Title Game (Giants - the Plaxico Game), 2011 Div Round (Giants), 2013 WC Round (49ers). All really awful weather and one where the winner had a bruising running game in horrific conditions. Green Bay didn't have any of that. The 2010 NFC Title Game in Chicago was played in similar conditions. Green Bay runs no-huddle to start, jumps to a 14-0 lead and then McCarthy hits the breaks. They needed the Raji INT for a TD to clinch it against... Caleb Hanie.
This is what concerns me - Green Bay's historical inability, under McCarthy, to switch from their "dome team" offense to a plan that wins in the post-season. If Green Bay was on the road at Carolina, Arizona or Detroit, I'd feel great about their chances this weekend. Much better than I do when they're home against Dallas when the wind chill will be around zero. Just look at 2010's playoff run. Rodgers lit it up in Atlanta and the SB in Dallas. He merely hung on against Vick in Philly and Cutler/Hanie in Chicago. Radically different offenses.
When McCarthy signed his extension, I don't think there was elation with fans, probably more of a sense of, "well, okay." He seems to have given more control over to Rodgers on late-game decisions and this is a prudent move. Far too often, McCarthy would force the run while leading late, getting stuffed, punting and other team regaining the lead late - forcing Rodgers to try and lead a comeback (hence, Rodgers' awful 4th quarter comeback record). I thought this would be the year the Bears would step up and Rodgers & McCarthy would finally have their big breakup on the sideline. Didn't happen. They actually seem to be getting along this year. Having Cutler on your rival and Caldwell coaching another helps any QB-coach marriage.
While in Green Bay, Holmgren only had three home playoff games and won them all in a fairly convincing manner -- his undoing was the three straight road losses in the playoffs at Dallas - a far more talented team from to 1993 to 1995. Note: Holmgren coached the Packers to three groundbreaking road playoff wins as well (1993 Detroit, 1995 and 1997 SF).
Once the Wolf/Holmgren building of the Packers was complete by off-season 1995-96, they had assembled an All-Star crew of locker room personalities. That '96 team was the first I ever covered as a professional. Favre, Chmura, Keith Jackson, Andre Rison (late season addition), Reggie White, Leroy Butler, Eugene Robinson and... Jim McMahon. (One note on McMahon. He was the cranky uncle the entire year, refusing to talk to media except for once in Week 17. He talked for 20 minutes by his locker and he was hilarious, glib, vulgar. He filled up our sportscasts for a week with his sound bites during a slow time.)
That 1996 locker room policed itself -- anyone could have won with that team.
That loss in Super Bowl 32 (San Diego to Elway's Broncos) took the Packers organization a decade to get over. They were 14 point favorites and assumed they'd romp to a repeat. It didn't happen. The next year was like the last hour of Boogie Nights. They knew the best days were gone, the window had closed. Favre had more influence (which wasn't good), the older leaders left or got hurt, Holmgren was plotting his next move. I always contend it's too bad GB didn't win that second SB in 1997. Holmgren would have been lionized in Green Bay. Favre probably retires five years before he did, sparing us the annual Kiln drama.
I like Dallas to win this weekend. They'll be loose. Garrett will take the chances that McCarthy will freeze up on. You'll know, on the first offensive series, if Green Bay will lay an egg or not. If timing is off (wind?) between Rodgers and the receivers, they'll try to overcompensate and Dallas will probably win. Simple as that.