I definitely saw how effective routine bedtimes are when we were visiting our friends with their two boys under 3. Early evenings were extremely hectic with my friend trying to cook, feed both children, change nappies, and keep them from tearing the house apart. But once the boys were tucked up in bed, they could sit down to a leisurely dinner with their guests (us) and actually have a proper conversation. I'm not sure if they eat with the boys when they don't have guests, but either way they have a nice long evening to spend together afterwards. I thought it was a very practical way to do things, and I'm sure it helps the sanity.