When it comes to issues of application requirements, deadlines, whether the stated GMAT, GRE, and/or TOEFL minimums are strictly enforced, whether a school will take a late official test score report, deferral policies, etc. I may have an answer or may not. If I do have an answer to such administrative questions, it is always because I can back it up with an official source. I don't even trust my own past experience in many instances because policies change. This is not just to protect myself from being wrong, but because I know I will best serve my clients sometimes by saying, "I don't know the answer to this question, but admissions will be able to provide to you. Please contact them."
One of the most extreme policy changes that I know of occurred when Oxford Said MBA program changed its TOEFL and IELTS requirement policy for admission in 2010. The prior English requirement was not stringent or necessarily stringently enforced. Suddenly for admission for fall 2010 and subsequently, applicants had to have the same high TOEFL or IELTS score required for admission to HBS: 109. Keep in mind that the UK's most prestigious and difficult to enter MBA program, London Business School, regularly admits applicants with a 100 TOEFL. As a result, the number of Japanese admitted to Said dropped significantly. Here in Japan, Oxford had been a popular 2nd choice school for top European MBA focused applicants and a first choice school for some applicants, suddenly became out of reach. The amount of misinformation at the time was significant with one of my own clients even refusing to believe that this policy would be enforced because colleagues from his company in past years had always been admitted and because some Japanese admissions counselor told him it would not be a problem, which it was.
His test score was nowhere near the required level and he went elsewhere. Given that university-wide policies change, that admissions directors change, and that the rules of any organization change, past precedent is not always a sufficient guarantee.
When it is possible to ask admissions, I say ask. Like when buying any expensive thing, you should be an informed customer. After all, a graduate degree is likely to be one of the most expensive things you will ever purchase.
Contacting admissions: I think if your question is relatively simple and not very specific to you, one of the easiest things to do is call the admissions office. Sometimes they can provide an immediate answer to your question. It is also fine to just send an email. With email, I suggest you keep the email short and to the point and state it in the form of questions. Simple, short, polite, and clear communications are best. If you have a personal and/or complex issue, you should certainly still try to explain it as clearly and simply as possible. If you feel like you received a response from someone who did not understand, try to follow-up. It is certainly the case that the first person to respond to an inquiry might be the least qualified person in the office, so you may have to work your way up the organizational pyramid. It is also a perfectly reasonable thing to ask questions at information sessions, either during the Q&A or privately usually at the end of the event.
Frankly, some admissions offices are friendlier than others. Just as some admissions offices will be better managed than others. School ranking does not necessarily correlate well with the quality and kindness of the response you receive, so don't be surprised if the admissions office at a high ranking school has worse customer service than one a lower ranking program.
Some applicants will no doubt worry about their contact with admissions being tracked or having some sort of bearing on applications. Unless one does something rude, this is nothing to worry about. In fact, it can be helpful to have such interactions, especially with smaller and/or friendlier admissions offices. Depending on the interactions, just as with campus visits and off-campus information sessions, your questions to admissions may even become a small topic discussion in an essay ("I was really impressed with how Ms. Johnson actively explained your program would..."). The more standard the question, the less likely the admissions office will even consider tracking it. Some programs do even extensive tracking of all potential applicant interaction, while others don't. Such tracking does not necessarily correlate well with admission results.
Finally, always keep in mind that admissions officers have two primary functions:
1. They are gatekeepers who select applicants for admission.
2. They are marketers and salespeople of their programs who need to try and make sure that they get the best possible applicants to fill up all the seats in their program.
Applicants have a tendency to focus only on the first function and put admissions officers up on some kind of pedestal as judges. Knock them off them off the pedestal! To better understand admissions officers, see here (Though this piece is focused on US admissions officers, it applies more widely). Assume that admissions offices are happy to answer all reasonable questions about their policies because this will help to facilitate the potential admission of qualified candidates to their program.
I am a graduate admissions consultant who works with clients worldwide. If you would like to arrange an initial consultation, please complete my intake form. Please don't email me any essays, other admissions consultant's intake forms, your life story, or any long email asking for a written profile assessment. The only profiles I assess are those with people who I offer initial consultations to. Please note that initial consultations are not offered when I have reached full capacity or when I determine that I am not a good fit with an applicant.