That was sort of a trap. It's considered bad practice in academia to bypass the committees and speak with the professors directly. Professors usually say in their home pages something to the effect of 'if you want to do research with me, apply to the school, do not contact me directly, I will ignore you'.
I've never seen such a note, and I've known several people who got into a department by talking directly with the professors there. I'm sure there is a difference between asking idle questions or trying to ingratiate yourself and posing specific informed, research-oriented questions because you're honestly interested, though.
I have seen such notes, but you have to take them with a grain of salt. When a department posts a note like that it's sort of the corporate equivalent of "Don't talk to our managers: submit your resume on this web form right here." So you should still talk to professors (but don't waste their time).
When a professor writes that on his/her personal/research website, it means "I already have grad students coming out of my ears, and I don't have enough grant money to support even half of them." This is useful information, because you (should) pick a grad school based on who you want to work with. You need to look elsewhere if all the professors you want to work with at a particular school are over-subscribed. Some professors also become jaded by the sheer number of unqualified candidates who can't hack it: None of the string theory groups in my school will talk to you until after you've been admitted, gotten good grades for a couple semesters and the passed department's second-year screening exam with a good score.
Let me part with this: I got into grad school (probably) mostly because I sent an email to the professor who ended up being my research advisor. I described what I did in the past (which was sorta-kinda tangentially in the same field), omitted any mention of my (not very good) grades, and asked a non-time-waste-y question about the research group. The thing about grad school (at least in the hard sciences) is that one of the criteria for admission is "doesn't anybody want this candidate in his/her research group??" When you have someone pulling for you on the inside, getting in is a whole lot easier.
Really? I know someone who got a PhD position by doing just that. Talking to a professor directly seems like a great idea as long you're sure you're not wasting their time (i.e. that you're a suitable candidate).
Even if you don't get the position, there's still a lot of value to be had from a conversation (for both parties).
Or not cynical enough. They no doubt say that because it's expected, and/or because they don't want to be contacted by thousands of hopefuls. It doesn't mean it's true.
Odd, talking directly with my professor is what got me into my graduation thesis. I have never heard of this as "bad practice." Then again, I've not heard of a lot of people looking at peoples grades as big factor for hiring, yet a lot of people here seem to think this is the case. So maybe I'm just lucky.
