A Cre8asite Forums member contends that optimizing for certain keywords isn't desirable any longer. The reason given is that people aren't ever searching for those keywords (even though it looks like a logical search term). He adds that there's no consistency in users' search patterns. The behavior differs from one searcher to another, which is entirely understandable.
If I had 'optimised' the page for MY keywords I may have lost all those visitors and THEIR keywords.
But another forum members suggests that you start optimizing based on the search phrases people use; you might even get better traffic. You need to think of what people are searching for and lengthen your articles so that you capture that desired traffic.
So should you not optimize for the original keyword list? You might want to still consider users who search for "the head and the long tail," as Ammon Johns puts it.
There's really good information here, so have a read at the forum discussion at Cre8asite forums