What happened in that excerpt is hopefully rare -- hopefully -- but the point is, there are no safeguards in this industry to keep things like this from happening, or to punish producers who pull stunts like this. In that actress' situation specifically, what I bet happened is that the producer did take her briefly through the script and said, "Hey, we're going to have you do A, B, C, and D." But the funny thing about sex is that it's something that has to be judged as it's felt in realtime. A line can be crossed in the middle of a fully agreed-upon act. And the moment a line is crossed on a porn set it is an act of rape, fair and square. Any person in polite society should be afforded at least the protection of personal judgment over where his or her "lines" are, which is probably the best we can do legally; the fact that we hear about porn actresses (and perhaps actors) going forward with shoots like this at the behest of directors shows they are, indeed, valued less than "normal" human beings by the directors. The moment she said "I don't think I'll be able to do this..." while she was in the middle of whatever act it was, the shoot should have stopped. No ifs, ands, or buts. Male and LGBT actors should be afforded the exact same protections. The fact that that one actress felt compelled to continue despite her own discomfort tells us, for certain, that something's wrong here. Sure, this guy's studio was raided a couple times. But he is still operating. The porn industry has the same implicit understandings with our government that other industries do, or at least that's my suspicion.
There's no reporting structure if the consumer suspects something's up (there are literally scenes out there where women actually seem to refuse very clearly, but the director quips something like, "Hey, you just need to loosen up, baby!" -- who you gonna call to find out if that was a real act of rape, or just staged?); and since pornographic actresses are basically treated as contract workers and not unionized ones to my understanding, they can probably just be tossed by the wayside in favor of more willing participants: this lends the cruel edge of severe economic competition to the decisions they make about their bodies. I know nothing about homosexual pornography (and lesbian porn produced for men hardly counts), but I'd have to take a wild guess that some of the same problems exist there as well.
The porn industry has a stake in reducing the conversation surrounding it to a binary "prude/not prude" level. Just as any capitalist corporation in its right, one-track-profit-motive mind, will more often than not resist unionization, so it is with porn, probably. The easiest way to avoid this is shape the nature of the debate itself. When Penn and Teller bring Gail Dines onto their Bullsh!t show and then drown her out with bombastic appeals to freedom, then proceed to play soft core porn clips and literally label her a "prude," they're egregiously skipping over issues that need to be discussed, and both sides would probably agree to discuss things like this constructively if they would just sit down and actually communicate. Imagine the actress in that article returning to her union after experiencing that and reporting being pressured on set, and suddenly all the porn workers in California go celibate until some serious action is taken by the industry. Now, maybe that's some sexual liberation.