Using Specified Path in XPath Searches
When making an XPath reference to data, using a specified path is more efficient than a "//" search, and the potential difference in processing efficiency can be marked.
Although using the "//" search will work, it requires more system resources to complete the search.
For example, because a "//" search finds every possible node that matches the selection criteria, looking for nodes called 'PrimaryDocument' returns every element (regardless of how deeply nested it is) called process data. This extensive search requires every element in process data to be examined. If the search is done within a loop, processing can become significantly slower as the size of process data increases.