The DH is helpful in allowing one to understand, for instance, that there are two origins narratives in Genesis. The best book on the topic, which is quite readable, is Friedman’s “Who Wrote the Bible?” The Genesis topics of main interest to the Biologos crowd are the creation narratives and the flood narrative. Fortunately, the DH argues that these are both the product of just two authors, J and P, and the editor. Questions about E and D are thus moot. The Europeans are biblical minimalists, and argue the whole OT was written in post-Exilic times. The arguments against this position are many and quite convincing. Conservative evangelical scholars such as John Walton provide good, insightful books without using the DH. However, I feel they lose significant insight by ignoring it. Opponents in the U.S. such as Wenham use literary arguments - but these always look to be quite weak.
The real test for the DH appears to be the flood narrative, which is a complex interweaving of text from both J and P by the editor. As with the two creation narratives, J and P had different theological reasons for their separate versions. The poor editor then had to combine them into a somewhat coherent tale. The resulting calendar is a mess to follow, which is further complicated by the editor’s own decision to add to it.
The bottom line is the DH is an example of progressive revelation, and as such is in line with the 1978 Chicago Statement on Inerrancy. it is thus not automatically to be avoided by evangelicals - although the more conservative members view it that way.