Yes, in general you should focus your efforts on one or two phrases on a particular page. A page can rank well for multiple phrases, however they are usually secondary variations of the term you target.
Thank you for the reply........I was taking a look at the Themes discussion section, and I am beginning to think that this particular approach caould be very useful and a good way to keep thigs organized.......do you have an opinion on this matter? -A Gerhart
I agree that the more specific and fine-tuned your page is to the keyword, the better. Theme optimization suggests to me that you take it down to the smallest or most specific point and then build back through your themes to connect it to the whole. For content on the keyword page itself, I’m sure to throw in as many alternative keyword phrases as I can without messing up the content or density of the page. Really follow your logs and determine what words folks are actually using to get to your page. You may be surprised by the alternative phrases and the actual traffic those phrases bring in.