I would give Watson a B on play calling. We had a healthy run

ass ratio. In spite of not scoring any touchdowns, we were able to move the ball fairly well against arguably the best defense we've seen this year. And our pass plays would've been much more effective if our QBs would've made better throws and/or better decisions. Two crucial pass plays come to mind immediately: Martinez INT, and the 3rd and 7 pass that was broken up forcing us to settle for a field goal to tie the game at 6.
Martinez INT - he has connected a few times with Reed on that exact play several times this year, and on every one of those connections Reed ran a skinny post, and that was the route he ran again tonight. But for some reason, Martinez threw it like Reed was running a straight-line seam route. That was a perfect play call at that time, and could've even been a TD to put us of 10-3. The INT was completely on Martinez' shoulders, not Watson.
The 3rd and 7 pass to Kinnie that was broken up - while I think the initial flag (PI on aTm CB) was legit and should not have been waived off by the refs, I think Martinez made a poor decision to pass it to Kinnie in the 1st place. After replaying the routes on that play, I noticed McNeil ran a beautiful corner route behind Kinnie, and he had his man beat by 2-3 yards for what would've been an easy TD and huge blow to aTm.
These were game-changing plays that Martinez will learn from. And they were the right play calls by Watson. In fact, I'd say when Watson did call a pass play, they were solid, especially the slant routes and the out patterns. We converted several key 3rd downs on good pass plays.