Personally, and I do NOT say this to belittle anyone who struggles with these teachings, I don't think the teachings themselves are all that difficult to understand.
I think the problem is "uninstalling" the programs of thinking that we've downloaded from the mainstream culture. I know that 2 years ago, when I first started looking into Catholicism, I did not grasp the logic behind the Church's teachings on issues of life and sex, but they seemed so minor to me that they really weren't on my radar.
But then I really undertook a study of the Theology of the Body, read books on it, listened to EWTN shows, and started to learn for the first time what it means to be human, what humans were supposed to be (original justice), how these issues fit into the big picture. Now I see that they are not just little bunny trails where the Church is being picky and moralistic; they are really essential to living authentic human lives and building a truly human civilization.
The reason why the Theology of the Body is so detailed is not because the concepts are difficult in themselves, but because we have so much re-learning to do. We don't see ourselves as we truly are and as we were meant to be, and it was JPII's mission to correct our vision..
No, I don't understand anything as deeply as JPII did. I'm only 18, how could I? But I don't think these truths are beyond the reach of the layperson, if he is shown the way.