Yes, It is too reactionary IMO, remember its only 1 week we got a lot of season left. Its easy to forget that patience is the most important trait you can have with fantasy situations like these. Yes, we know Mixon is the best back, but he does have to prove it in a game. I have no doubt that the cream will eventually rise to the top but, we(coach and fans) need to see it first so they can justify bumping up his share. I was in the camp that said, Mixon was a third round talent and still see him as such but, you have to wait until it becomes clear.
If you own him you should get ready for a potentially long wait, but by week 5 I expect results. Best to try and buy him now for a Jstew or some other low end RB2 or RB3 to get a potential difference maker for this year. He's dynamite for redraft. Dynasty its even better yet.