Lead architect Blaine Cook helped build Twitter into the downtime-prone morass it is today. Now, as the service grows ever more popular, and ever more unreliable, he's out. In an email to Silicon Alley Insider, Cook says he left Twitter over two weeks ago and plans to move to the U.K. with his partner. "We're Canadian and her visa makes it impossible for her to work in the U.S.," Cook explains. SAI's Peter Kafka wonders if Cook actually got the boot due to Twitter's many outages. We think it's more likely that, as close to Twitter's groundswell as he is, Cook has seen what Twitter hath wrought and is wisely fleeing the country before Robert Scoble tests the limits of how many Twitters one human — or other creature — can send in a day.