How to make it go away....
Get lifting shoes! Yes this helps because of the lift it gives you. Yet it's not really practical for air squats.
Oh, before I forget. Why is butt wink bad? Am I making a big deal about something that's not a huge deficit?
Simply put you lose your lumbar curve in the bottom of the squat. Also it shows inflexibility. My desire is to be able to go into a squat as up right as possible. Any pull under movement in my spine is a lose of control and I don't like that and it's also going to be a weak link in my squat.
After reading many threads on Butt wink the cue that's given over and over is to pull yourself into your squat. To work this slow, to not drop into the squat. This would be something that you work on outside of your WOD's.
Any input on this would be great...hows your butt wink?
Side note: This has nothing to do with Butt wink but lets think Crossfit Kids