The DOM assumes that the XML document being processed is well-formed, but makes no assumptions about its validity. Because there is no way to represent validity without departing from the DOM Level 2 standard, the Arbortext Editor DOM interface ignores context checking. Therefore, it is possible for the user-written program to make a document invalid that was previously valid. However, users can context check the document once the user-written program returns control to Arbortext Editor. Alternatively, the user-written program can use the Acl interface to perform context checking.

The DOM allows users to create NodeList objects that contain pointers to every tag with a given name in a document or document subtree. Once created, a NodeList is dynamically updated to reflect every tag insertion or deletion. The existence of these objects is likely to slow tag insertion and deletion in Arbortext Editor. Users should delete NodeList objects as soon after use as practical.