My brother-in-law works on that principle, but only for 50% of his clocks. On top of that, he has his favourite clock set fast so he isn't late for buses, and he never corrects the others so they gradually become faster or slower. In one room, I can see about 5 clocks showing times spread over about 75 minutes and the only one that I can trust is the display on his digibox!
On top of which, neither he nor my sister know how to set the alarms on their various clocks so they have a 'getting up at 06:30' clock, a 'getting up at 08:00' clock, and so on. One of them always goes off at midnight. I asked why, and b-i-l said that it was to remind him to watch a TV programme in 2004 but he's lost the instructions and doesn't know how to turn it off!