The bar walkouts are a good all-around stabibilty thing. And getting you used to holding heavy weights.
In that way they are also a good way to get ready to start heavy squatting again...especially since you can hold more weight than you can squat. Forgetting what it feels like to support those heavy weights can actually make you fail when you do go to squat again. The 'shock' of the weight will basically shut your body down sensing injury potential. It's not just the core supporting muscles needing to be kept up it's a psychological thing....the last thing you need to be thinking is how unbelievably heavy a weight feels right before you try to squat it