diff --git a/java/src/org/broadinstitute/sting/gatk/GenomeAnalysisEngine.java b/java/src/org/broadinstitute/sting/gatk/GenomeAnalysisEngine.java
index 2b0a7e2db..cff23ca8b 100755
--- a/java/src/org/broadinstitute/sting/gatk/GenomeAnalysisEngine.java
+++ b/java/src/org/broadinstitute/sting/gatk/GenomeAnalysisEngine.java
@@ -210,9 +210,9 @@ public class GenomeAnalysisEngine {
                 long toPruneSize = includeSortedSet.coveredSize();
                 long toExcludeSize = excludeSortedSet.coveredSize();
                 long intervalSize = intervals.coveredSize();
-                logger.info(String.format("Initial include intervals cover %d bases", toPruneSize));
-                logger.info(String.format("Excluding %d bases from original intervals (%.2f%% reduction)",
-                        toExcludeSize, (toPruneSize - intervalSize) / (0.01 * toPruneSize)));
+                logger.info(String.format("Initial include intervals span %d loci; exclude intervals span %d loci", toPruneSize, toExcludeSize));
+                logger.info(String.format("Excluding %d loci from original intervals (%.2f%% reduction)",
+                        toPruneSize - intervalSize, (toPruneSize - intervalSize) / (0.01 * toPruneSize)));
             }
 
         }
@@ -295,7 +295,7 @@ public class GenomeAnalysisEngine {
      * @param walkerType Type of walker.
      * @return Name of the walker.
      */
-    public String getWalkerName(Class<Walker> walkerType) {
+    public String getWalkerName(Class<? extends Walker> walkerType) {
         return walkerManager.getName(walkerType);
     }
 
diff --git a/java/src/org/broadinstitute/sting/gatk/executive/HierarchicalMicroScheduler.java b/java/src/org/broadinstitute/sting/gatk/executive/HierarchicalMicroScheduler.java
index 494c534d6..4ac840d29 100755
--- a/java/src/org/broadinstitute/sting/gatk/executive/HierarchicalMicroScheduler.java
+++ b/java/src/org/broadinstitute/sting/gatk/executive/HierarchicalMicroScheduler.java
@@ -96,7 +96,7 @@ public class HierarchicalMicroScheduler extends MicroScheduler implements Hierar
     public Object execute( Walker walker, ShardStrategy shardStrategy, int maxIterations ) {
         // Fast fail for walkers not supporting TreeReducible interface.
         if (!( walker instanceof TreeReducible ))
-            throw new IllegalArgumentException("Hierarchical microscheduler only works with TreeReducible walkers");
+            throw new IllegalArgumentException("The GATK can currently run in parallel only with TreeReducible walkers");
 
         // Having maxiterations in the execute method is a holdover from the old TraversalEngine days.
         // Lets do something else with this.
diff --git a/java/src/org/broadinstitute/sting/gatk/executive/MicroScheduler.java b/java/src/org/broadinstitute/sting/gatk/executive/MicroScheduler.java
index 6b39852ca..af3befc82 100755
--- a/java/src/org/broadinstitute/sting/gatk/executive/MicroScheduler.java
+++ b/java/src/org/broadinstitute/sting/gatk/executive/MicroScheduler.java
@@ -37,7 +37,9 @@ import org.broadinstitute.sting.gatk.iterators.StingSAMIterator;
 import org.broadinstitute.sting.gatk.iterators.NullSAMIterator;
 import org.broadinstitute.sting.gatk.Reads;
 import org.broadinstitute.sting.gatk.GenomeAnalysisEngine;
+import org.broadinstitute.sting.gatk.WalkerManager;
 import org.broadinstitute.sting.utils.fasta.IndexedFastaSequenceFile;
+import org.broadinstitute.sting.utils.StingException;
 
 import java.util.*;
 import java.io.File;
@@ -80,10 +82,13 @@ public abstract class MicroScheduler {
      */
     public static MicroScheduler create(GenomeAnalysisEngine engine, Walker walker, SAMDataSource reads, IndexedFastaSequenceFile reference, Collection<ReferenceOrderedDataSource> rods, int nThreadsToUse) {
         if (walker instanceof TreeReducible && nThreadsToUse > 1) {
-            logger.info("Creating hierarchical microscheduler");
+            if(walker.isReduceByInterval())
+                throw new StingException(String.format("The analysis %s aggregates results by interval.  Due to a current limitation of the GATK, analyses of this type do not support parallel execution.  Please run your analysis without the -nt option.", engine.getWalkerName(walker.getClass())));
+            logger.info(String.format("Running the GATK in parallel mode with %d concurrent threads",nThreadsToUse));
             return new HierarchicalMicroScheduler(engine, walker, reads, reference, rods, nThreadsToUse);
         } else {
-            logger.info("Creating linear microscheduler");
+            if(nThreadsToUse > 1)
+                throw new StingException(String.format("The analysis %s currently does not support parallel execution.  Please run your analysis without the -nt option.", engine.getWalkerName(walker.getClass())));
             return new LinearMicroScheduler(engine, walker, reads, reference, rods);
         }
     }