If we can manage to get at least twelve expert articles per year, then we can have a new expert-written Featured Article each month, highlighted under a suitable heading on the Main page with a direct link from there to the whole article and the related community article.
Having expert-written articles will hopefully raise our credibility amongst the academic psychology community.
However, if we replaced the community articles with expert-written ones, it wouldn't really be following the spirit of wiki writing, which is why we believe that having separate expert articles (in parallel to community articles) would be the best way forwards. This way we get the advantages of both approaches, while minimizing the disadvantages.
The expert articles would inform the general reader and hence raise the quality of the community articles. Likewise, the community articles may actually contain information which the expert had not considered. There may be related concepts or perspectives in other papers, for example, that the expert had not encountered. Furthermore, an interpretation of their article by another reader might give them an idea that they may not have already had. All of our research and ideas come from reading other people's ideas.
Attracting expert guest writers will also attract more expert guest writers (and more contributors), thus, in turn, further raising our readership, contributorship, and credibility.
Expert articles are protected from general editing. If expert articles were not protected, then people would come back (eventually) and change what the expert had written. This irritates most experts immensely, as most experts are better qualified to write the article than most other contributors (even on this wiki). This is one of the chief complaints about Wikipedia by experts who have taken the time to contribute there.