I certainly can't speak for everyone's experience with the border officials, however I'm sure that their jargon might create some difficulties for you.
As far as "knowing all the countries," I've been across some borders where I've had to explain their own visas to them. For example, the type of visa and residence permit I had while I lived in China (specifically relating to multi-entry vs. single entry.) I've been held up at the border crossing leaving Korea for Japan because they assumed I needed a "release letter," which in fact wasn't the case; discovered only after 2 hours of being detained while they contacted my former employer. Crossing into Mexico, specifically at the inland military checkpoints, I've also have had occasional difficulties, resulting in a required "donation" to prevent my fully loaded car from being searched down to the axles. (I have family in Guadalajara and Texas, so I've made that drive frequently.)
I don't care if a border official knows Zaire from Angola -- just as long as they know the rules and regulations and apply them systematically to visitors.
Never a problem when I've gone to Serbia, but given their problems with cybercriminals, if I told the border guard that I was there to hang out with computer hackers, I suspect I'd have a rough time.
My point is that this knee-jerk insulting of US border agents is childish. You don't know "most" of them, so you have no basis for your statement. As far not being well educated, a bachelors degree in law enforcement, criminal justice, political science or accounting is generally required for UCIS agents, among other things. The fact is that you just don't like them for whatever reason, an opinion to which you are entitled, but don't mistake your bias for actual fact.
Spend some time crossing borders around the world, especially in former Soviet countries, East Asia, Latin America, then come back and make the claim that US border agents are somehow less intelligent than you would like. Try border crossings in Lebanon or Saudi Arabia. Cross the border from Serbia into Kosovo as a non-Serbian/Kosovar citizen. The Chinese border can be loads of fun, especially at a land crossing. The UK can be especially rough depending on your nationality, though admittedly, I've always just sailed through the line.
As far as the school's name change, the comment about 30% of their attendees cross the border to go there. Is there any data or facts regarding the "hard time" those people had? Just saying it was "difficult" doesn't really explain how it was difficult. Where entries denied based exclusively that they were attending Hacker School? I'm not sure what the "difficulty" actually was. And since Hacker School isn't an actual SEVP educational institution that can sponsor student visas, then that would mean they have students studying as part of their organization on tourist visas, which is against the rules of the tourist visa. It also is against the rules of the Visa Waiver Program to enroll in any kind of educational institution -- degree granting or not.
So that begs the question: where the problems with immigration because visitors where entering the country with a purpose inconsistent with their visa? I think that explains more than the institutions name. However, if Hacker School is representing itself as a self-improvement center, then of course a tourist visa would work, however that wouldn't explain the border problems since a tourist visa does not require a declared itinerary -- so Hacker School would never be a required part of the border entry formalities.
I'm wondering what legal basis is being used for the attendee's visas. If it's a job training program, then that is considered "vocational" training and that requires an "M" visa. Short "recreational" study is permitted under a B (tourist) visa, however Hacker School isn't recreational. Their compensation is from recruiting employees, which puts it into a different category than taking a yoga class.
I personally think what HS does is great and I support them, but I do think that international attendees ought to be very, very careful when it comes to the visas. Misrepresenting or having a stay inconsistent with your visa status can result in a permanent entry ban if caught. The smart move for Hacker School is to get certified by Homeland Security, then they'll be able to sponsor student visas. If anyone's interested in what schools are legal, here's a link: http://studyinthestates.dhs.gov/school-search?field_school_n...