I agree it's a pain, but I work in the industry and most people I have known don't quit without another job lined up. Facebook gives 21 vacation days; Google (relatively stingy) gives 15 or more. Plus you can call in sick (I don't recommend this but if you're out the door anyway it's an option). I just don't think it's good practical advice to follow the procedure in this article.

Yep. Say you have ten days of vacation per year (welcome to the USA!) This means you can “get serious” with max 10 companies per year. I’ve in the past interviewed with that many companies in only a month! You need to be very creative with your time to do serious interviewing while still working.