Please Dont Follow Any SEO Technique Other Than White Hat.
I have not heard about Grey Hat SEO yet. It is new to me. But If grey hat seo is something what you all are saying, i.e. mix up of white and black hat SEOs, then I wont give it much preference, because it wont be supportive on long run for a site's SEO performance. Today may be some black hat seo techniques are not recognized by google , but as you all know google's webspam team is continuously making its search algorithm better and better so in future , any such unrecognized black hat seo techniques will create massive problem to the site's internet exposure, may result to ban even in fatal cases. So be careful of it.
Gray Hat SEO is about risk versus reward. Are classified as a large number of solutions within the SEO SEO Tools gray hat. Some gray hat SEO services tend to use more dubious devices and take greater risks. While some gray hat techniques to a large extent may obey the rules of the search engine, other land you in trouble and you need to seriously consider and necessary precautions before use. Gray Hat SEO techniques remain unspecified by all the Google SEO guidelines.