Couple of things to note
1) MNF schedule is pre-determined and can't be flexed. Schedule is based off previous year so if a team nose-dives ain't sh!t you can do to change the schedule. MNF is no longer the marquee night to watch football anymore.....
2) SNF is the marquee night, and with the flex schedule, it has the ability to keep quality match-ups late in the season. NBC has the best football contract if you ask me. They don't have to compete with anyone in their time-slot and they routinely have the best match ups. Not to mention the kick-off game on Thursday and now the Thanksgiving primetime game.
3) So we get Thursday football from week 1 (kickoff game) all the way through week 15. IF my math is right that is 17 Thursday night games (3 on Thanksgiving). That means at least two teams will play Thursday night games twice. My guess is the teams in the kickoff game will have play on Thursday again later in the year.