Allinanchor seems to show approximately where my serps are for certain keywords. So the obvious thing is to increase my allinanchor value. Can this be done onsite or must it be offsite? I have considered adding more pages the use this keyphrase in the anchor text. Each page will be slightly different. Shouldn't this improve my allinanchor rating and in turn should improve my serps for the given keyphrase?
I don't know that adding more pages to the site and using the anchor kw will increase rankings much. You will get more out of having the link on another site. As long as we are on the subject, allintitle:, allintext:, and allinurl: also have a strong correlation to ranking. Be sure to use your keywords in the title, the url, and tweak your content to up the density - but check your competition's sites, don't overuse the kw. These are things that you can do right away to help your rankings.