HTCondorWiki: Sub Dags Vs Splices

-Note:  In the process of creating this document (2016-06-13)
+Note:  In the process of creating this document (2016-06-14)
 
-Note:  This document is valid for HTCondor version 8.5.5.
-
-This is a comparison of the features of external sub-DAGs and splices
-(see
+This document is an explanation of why you might want to use the DAGMan external sub-DAG and splice features, and which one you might want to use in a particular situation.  (See
 {link: http://research.cs.wisc.edu/htcondor/manual/v8.5/2_10DAGMan_Applications.html#SECTION003108900000000000000}
 and
 {link: http://research.cs.wisc.edu/htcondor/manual/v8.5/2_10DAGMan_Applications.html#SECTION0031081000000000000000}
-for detailed information).
+for detailed information about external sub-DAGs and splices,
+respectively.)
+
+
+Both external sub-DAGs and splices allow you to compose a large workflow from
+various sub-pieces that are defined in individual DAG files.  This is the
+basic motivation for using either external sub-DAGs or splices:  you want to
+create a single workflow from a number of DAG files, either because the
+smaller DAG files already exist, or because it's easier to deal with
+sub-parts of the workflow.  (One use case might be that you have sub-workflows
+that you want to combine in different ways to make different overall
+workflows.)
+
+*Feature Comparison*
 
 Here's a table comparing external sub-DAGs and splices.  Note that the bold entries are the ones that are advantageous for a given feature.
 
@@ -43,4 +53,6 @@
 
 *How to use external sub-DAGs to reduce workflow memory footprint*
 
-(add stuff here)
+(Coming soon!)
+
+Note:  This document is valid for HTCondor version 8.5.5.