I personally love my religion classes. I'm taking one about the Old Testament and you will never, ever, be "finished" in your learning about faith. I've found that the more I dive into it, the more I get, regardless of how many hours I've already put in.
No, BYU students are not particularly dense. While BYU is no Ivy leaguer, it's ranked pretty highly in a lot of aspects.
The beards thing is essentially the idea that students should look presentable and "neat and clean" as the honor code states. While many beards would be fine by that criteria, I think the honor code wants to prevent against the wild 2 foot long type beards. There's a lot of people who don't like this aspect of the honor code, but it is what it is.
As to so called "soaking" and "humping" the answer is that it does not happen. I've seen this brought up many many times, and in all my 3 years at BYU, I've never heard of any such instance of it. To me, and many others, it's pretty clear cut, if you're "soaking" or "humping" you are clearly violating the law of chastity that we believe has been given to us. I think that those who would participate in those kinds of activities either: Don't go to BYU, or just have sex and probably end up getting kicked out.