Not necessarily objecting to the whole thread (I admit I didn't finish it), but I hate this style of argument where one makes a number of steps in the argument and they present a key "linchpin" of that argument as some sort of axiom, but with nothing to back it up:<p>> Think of the last time you had a bad night sleep. You feel bad the next day, but the next night if you sleep well, you'll feel fully recovered from that bad night. <i>But when we spring forward, we often feel bad for weeks</i>. Why does losing that hour have such a profound effect? It is because we are shifted into a state of permanent jet lag with the time change. Your circadian clock follows dawn. The dawn on March 13th in Calgary is at 6:53am, but on DST the next day it is at 7:51am.<p>(I emphasized the relevant sentence)<p>I certainly don't feel bad for weeks after the start of DST, I literally don't know what he's talking about. And, if anything, if I feel sleep deprived it's usually because I go to sleep later because I much enjoy having an extra hour of daylight in the evening.