There are three elements here. First, we want an actually credible, worthy of amplification person or persons to create the content. Why is that? Well, because if we do that, we make amplification, we make link building, we make social sharing way more likely to happen, and our content becomes more credible, both in the eyes of searchers and visitors as well as in Google's eyes too. So to the degree that that is possible, I would certainly urge you to do it.
"I wanted to thank you guys for everything you've done for my company. When I first went to Curt for help about a 1.5 years ago, I was a very tiny company. We're now doing about 1500 jobs a month, and I give a lot of credit to you guys for the exposure. It's been life changing for me. I was working 12 hour days, 7 days a week for 2 years. I am finally able to back off some because I can afford office help as well. Thanks for being so great at what you do. I still don't know what that is exactly, but thanks for doing it so well."
In theory Google doesn't take note of descriptions. [And yet Google highlights keywords in descriptions.] But the greatest effect of a good description is click through rate, which is a ranking factor. So if your description is a good call to action and people click on it then Google will notice and (assuming people don't bounce from the site because the content is no good) your ranking should increase.
Analysis is the key to SEO – Monitoring your ranking on search engines is key to getting better results. Start by tracking the most important website metrics to set a baseline for your performance. Make small content changes and see if you notice a boost in your site traffic or rankings. Avoid making several unrelated changes simultaneously so you can always keep track of what was responsible for improved performance.
Additionally, there are many situations where PPC (a component of SEM) makes more sense than SEO. For example, if you are first launching a site and you want immediate visibility, it is a good idea to create a PPC campaign because it takes less time than SEO, but it would be unwise to strictly work with PPC and not even touch search engine optimization.