Keywords(phrases) searches do change over time.
I wanted to write this blog on how certain keywords can and do change over time.
Its true that certain keywords you are using hardly ever change in their search results. But here are a few that could be a higher or lower search result just months apart.
There are seasonal keywords that are obvious like Christmas. You would get different results in February than in December. Deer hunting in June as opposed to November. In my case Bingo.Wait,that never changes. Always 4,000,000 searches monthly.
The reason I'm writing this is that I went from page one all the way to page 6 because I changed my keywords in the title and in the first paragraph on all pages and post. 62 total. Lot's of work to be sure.
So my advice is since we are not sure what google is looking for(yes we are), I don.t think the spiders like you messing with the keywords down the road.
In the beginning, the spider/crawler likes you and you get a high ranking. Later, your website is stale and they don't like you because you are trying to fool them.
So get them right the first time. Do your research and searches on keywords, and get on page one,right up there with the majors. Learn all there is to know and become and expert on keywords. Do that and your future will be bright with any IM program, and 3-6-months later your still be on page one and getting traffic.
I just saw Carson e-mail on this same subject after I made this blog. Upcoming webinar on Friday to cover the four seasons of keywords.