Accepted into EPFL, might not get Visa in time, what am I signing myself up for? I was accepted to a Masters Program at EPFL 5 days ago. I am currently collecting all the necessary documentation to apply for a visa. However there is a chance it will take longer than I have to get to Switzerland (have to be there by September 30). My only idea right now is to use my passport to get to Switzerland as a tourist. Remain there until I get the visa (the 90 days are enough to guarantee that if I get approved I get the visa on time), cross the border to France, cross the border back again with the student visa.

Has anyone done something like this? Is this even legal? I tried contacting EPFL and the Swiss consulate and they were not helpful.

Additionally, EPFL wants me to sign a web form confirming or denying my attendance to the Masters program by June 30 (this weekend). They gave me essentially a week and a half to make the entire decision. Do I have any real obligation to stick to my word? If I say I want to go but it turns out I win the lottery or get into a different program afterwards I prefer and no longer feel like going to Switzerland will something happen? I.e what happens if I go back on my word (EPFL also was very unhelpful answering this question).
I know of international students in my research lab (in Canada, not Switzerland) that crossed the US borders and came back immediately to renew student visas. In itself, this is not illegal. 

However, I don't think that you would be allowed to study in your program without a student visa, because those are usually required by the university to receive insurance coverage (for instance, if you're working in a lab). You really should ask your program director for advice on this situation. I would expect them to be understanding and guide you.