Well, I don't mean up as in up at the ceiling or whatever - just up enough to keep my chest high, so that my back or neck wouldn't curve the wrong way during squats. I learnt how to use my back muscles correctly to stabilise. I'm not a chiropractor, or any type of expert - I'm just saying what my experience was. He did give me a whole lot of corrective stretches, which worked wonders. I've never had a problem again.
I gave up Smith squats, dropped the weight on regular squats, and have been completely anal about form ever since. And have made better progress. Anyway, the point is, having numb arms and hands is no joke, and I wouldn't fuck around with cervical nerves.