Don't do blackhat you'll just get your site banned or slapped by google and others. It may help you short term but not long term.

Black hat SEO technique helps to generate more traffic, but it is not good for a website.

Here are two things you can do to solve this problem. First, you can put your targeted keyword in your article title. It is extremely important as the title describes what you are going to talk about inside the article.

Black hat SEO can ruin your website in the long run. So I do do recommend that you practise it.

i am not sure whether it is useful or not

I think the excess use of black hat technique can harm your site tremendously. It can be called effective but for long term it should be avoided.

black hat techniques could harm your ranking..

If you can succeed without it why bother?

Mostly people use blackhat technique for fast result but the result is not secure for a long time.

You want to place the keywords strategically on your page. Get the keywords right before beginning any technical measures of SEO for optimizing your site.

No it is not useful because some times when search engine know about that then they banned your site for permanent.

It is the useful but for few times and when you caught by search engine it will be bad for your site.

Black Hat techniques can really hurt your site and there is seldom you don't get caught doing them as the search engines are quite intuitive nowdays and find just about everything.

Blackhat SEO technique is effective only for the short time. Using Blackhat SEO we can easily get the top ranking in short time. But the access use of such type of techniques is very dangerous for sites. Often Your sites are send to the sandbox or banned by the search engine's crawlers. Now a days blackhat SEO techniques are not so effective because of the new updates of search engines. So use the effective SEO techniques that follows the rule or policy of search engines to get top ranks.

I dont every like to be use blackhat SEO