Expand load caveat about Java and Cassandra filters

Author: johnsmartco

src/resources/cdm-detailed.properties

@@ -254,8 +254,10 @@ spark.cdm.perfops.ratelimit.target                40000
 
 #===========================================================================================================
 # Java Filters are applied on the client node. Data must be pulled from the origin cluster and then filtered,
-# but this may have a lower impact on the production cluster than the Cassandra Filters.
-# node may need to do a lot more work than is normal.
+# but this may have a lower impact on the production cluster than the Cassandra Filters. Java filters put 
+# load onto the Cassandra Data Migrator processing node, by sending more data from Cassandra. 
+# Cassandra filters put load on the Cassandra nodes, notably because Cassandra Data Migrator specifies 
+# ALLOW FILTERING, which could cause the coordinator node to perform a lot more work.
 #
 #  spark.cdm.filter.java
 #    .token.percent   : Percent (between 1 and 100) of the token in each Split that will be migrated.