First off, for those that are not familiar with the term "Black Hat SEO" it usually refers to highly controversial tactics used to manipulate the search rankings of a given web page and are generally in violation of search engine guidelines. Second off, if the title of this article seems strange to you, you're probably too young to have been exposed to the "Silly Rabbit, Trix are for kids" TV commercials. No worries. Your enjoyment of this article will not be affected.
On with the article.
If you think you should be using Black Hat SEO or you are missing out, I have only three words of advice: DON'T DO IT!
For those that are feeling unsatisfied with the brevity of this advice, and need more words, let me expand a bit more: BLACKHAT SEO IS NOT WORTH IT FOR MOST WEBSITES. Instead of spending a lot of time and money on black hat SEO, you're probably much better off simply doing things that makes your site and it's associated content more rank-worthy.
Let me say that one more time, for emphasis: The best way to optimize your website and get more/better traffic via search engines is to make the content on your site something people actually want to find. When you do this, you're working with the search engines -- not against them.
Reasons You Don't Want To Use Blackhat SEO
1. Real Black Hat SEOs Might Not Exist In Your World: There's a dearth of people out there that even get fundamental SEO, understand how the various search engine algorithms work and how to do more than just guess at the weight of various factors impacting search results. The number of people that actually know enough to employ really advanced black hat techniques is vanishingly small. The number of these people that you are probably associated with is close to zero.
2. Even if they exist, you can't pick them: Lets say for a moment that there are those elite few people that actually do know enough to apply these highly advanced techniques and you could connect to them. How would you know one if you met her? This is a bit like the public stock market. The chances that some fund manager has figured out a consistent way to "beat the system" are pretty low. Your problem is, even if they're out there, you wouldn't know how to separate those that make the claims from those that can actually do it.
3. Even if you can pick them, you can't hire them: Assuming you had some uncanny ability to really pick out the true uber-experts, chances are, you couldn't hire them because you couldn't afford them. If they're that good, they're either working on some super-big project for some mega-company that can spend some real money -- or working on their own private projects.
4. Even if you could hire them, their ideas may not work for you: There are many, many factors that go into search engine algorithms. Some are more important than others, but it's really, really hard to know whether a specific black hat technique will actually work for you. The more advanced the technique, the more likely that there are specific situations within which the technique works.
5. Even if it does work, it's probably temporary: Even if certain techniques do actually work today (and I'm sure there are some smart folks out there that have figured some out), the search engine algorithms are constantly evolving. Chances are, if somebody has found a "back door" to unduly influence the search results, this door will eventually be closed.
6. Even If It Lasts, It's Really, Really Risky: Assuming you could find some small edge and that will last long enough for it to be worthwhile, you have to balance this benefit against the risks that you're taking. Is a potential increase in traffic via organic search really worth risking having your site banned completely?
So, here's the build-up of arguments: You probably don't know someone that really has the talent to do black hat SEO well. Even if you did, you wouldn't know it. Even if you knew it, you couldn't hire them or afford them. Even if you could hire them, it probably wouldn't work for you. Even if it did work for you, it's probably temporary. Even if wasn't temporary, it's just too risky. Any questions?