Berkeley's on the semester system, so school starts on Tuesday, Jan 18th for me. If my New Year's Resolution were to go to all my classes this semester, I would fail within two days. Not because I'm lazy, but because I have grad school interview weekends that often start Thursday or Friday.
So I understand having interviews Thursday/Friday means professors at the school don't have to come in on Saturdays and Sundays, but for me, it means I won't be going to my Friday class for at least 6 weeks in a row. On at least 5 of those weeks, I'm going to be missing all my Thursday classes as well. And sometimes the Wednesday ones too, for those on the East Coast (and also UCSD). Wouldn't be so bad flying in the other direction, but I have to start 3 hours earlier here.
I still have one class I need for my major, a class I need in order to graduate. And I'm going to be missing almost 1/3 of the lectures for that class. I really have to talk to the professor too, because I recall correctly, the midterms for that class tend to be Thursday nights. Lovely.
So I'm flying across the country every other weekend, interviewing within California the other weekends, missing classes I'll have to catch up on, including one for my major, and trying to do research for my honors thesis at the same time. And I don't even get to go home every couple weekends to recharge.
I think I understand now why so many people take a year off. Here's my suggestion to future grad school applicants: even if you know what you want to study, and that you want to go to grad school, think hard on when to apply. If you're applying to a bunch of places that you think you have a pretty good chance of getting in to, and you still have requirements to fulfill during your last semester, it might be to your benefit to wait. Find an internship or a job for 6 months or a year, and apply the following spring.