That implies eating breakfast at work for most people. Also you need to be leaving work promptly at 5pm, not have too long a commute home and then start cooking

That implies eating breakfast at work for most people. Also you need to be leaving work promptly at 5pm, not have too long a commute home and then start cooking straight away if you want to eat dinner by 6.30pm. (I do this, but didn't pre-kids, and don't think it fits by default into most people's lives).