Twice a year, I let forth a stream of abuse at whoever will listen (and those who won't) to just leave the **** clocks alone!!
If school kids need more light on the morning or evening or whatever, then change the opening hours of the school. If farmers want more light, then let them get up earlier, and leave the rest of us out of it!
The number of appointments I've missed (who remembers the hilarious iPhone DST debacle last year? It automatically put the clocks forward, and handily moved every appointment in the calendar forward one hour), the number of people who are late for work, the chaos on the roads as everyone is rushing because they overslept, and crashing because they're exhausted and had to get up an hour earlier...
Where I live (in Aberdeen, Scotland) in winter there can be, as a previous poster noted, fewer than 5 hours of light, and when it's overcast, it's basically dark all day. Tweaking the clock back or forward doesn't make it any less dark, it just makes people tired, irritable, and late.
Let our body clocks adjust naturally, slowly, as they have evolved to do. I hate jet lag, I hate it most of all when I haven't even travelled.