So, I'd mentioned this in many of the ongoing threads related to this weekends game, but I decided to take a deeper look into it and see what comes.
SF Defensive Snaps Last 4 Weeks
@NE Defense: 92 snaps (W)
VS MIA: 55 snaps (W)
@STL: 68 snaps (Late into OT) (L)
@NO: 67 snaps (W)
Total: 282 snaps
Both Seattle and San Francisco have played 3 of their last four games on the road and both teams have won 3 of their last four games. The big difference I think, is that not only is SF coming to our house on Sunday, but their defense was on the field for a whopping 92 snaps. While our starters the last two games were basically sitting by the end of 3rd quarter.
The Niners have got to be gassed at this point, much like our team was gassed on that Thursday night game against the Niners after having to play the Patriots ourselves the previous Sunday.
I don't know if this is often considered or if it is how much weight is given to it, but I think this factor is going to be huge.