I think history is fairly clear with coaching expectations. Losing four in a row is a hot seat and that is a risk right now. Cost Brian Billick in 2007, remember when he lost to the winless Miami Dolphins, and Billick was on a new five year deal. Cost Cam Cameron in 2012 when the Ravens dumped four in a row after a 9-2 start. Others were on the seat too, I believe Flacco, Caldwell, and Boldin were all at risk, Boldin proved to not survive.
So starting this year 0-2 is hot seat. Harbaugh having his players study film on the plane, yea, there is some coaching hot seat for Pees. 0-4 and I believe Pee's is gone right after the game like it was for Cam Cameron. The fact that Harbaugh is mad may force Pees out at year end anyway, no matter what. Ladarius Webb is likely gone as well.