diff --git a/src/main/java/com/metaweb/gridworks/model/Cell.java b/src/main/java/com/metaweb/gridworks/model/Cell.java
index b20fbfd68..98ea25b37 100644
--- a/src/main/java/com/metaweb/gridworks/model/Cell.java
+++ b/src/main/java/com/metaweb/gridworks/model/Cell.java
@@ -75,7 +75,7 @@ public class Cell implements Serializable, HasFields, Jsonizable {
     }
     
     static public Cell load(String s) throws Exception {
-        return load(ParsingUtilities.evaluateJsonStringToObject(s));
+        return s.length() == 0 ? null : load(ParsingUtilities.evaluateJsonStringToObject(s));
     }
     
     static public Cell load(JSONObject obj) throws Exception {
diff --git a/src/main/java/com/metaweb/gridworks/model/Column.java b/src/main/java/com/metaweb/gridworks/model/Column.java
index 30da39aa8..67350cf00 100644
--- a/src/main/java/com/metaweb/gridworks/model/Column.java
+++ b/src/main/java/com/metaweb/gridworks/model/Column.java
@@ -118,7 +118,7 @@ public class Column implements Serializable, Jsonizable {
             column._reconConfig = ReconConfig.reconstruct(obj.getJSONObject("reconConfig"));
         }
         if (obj.has("reconStats")) {
-            column._reconStats = ReconStats.reconstruct(obj.getJSONObject("reconStats"));
+            column._reconStats = ReconStats.load(obj.getJSONObject("reconStats"));
         }
         
         return column;
diff --git a/src/main/java/com/metaweb/gridworks/model/Recon.java b/src/main/java/com/metaweb/gridworks/model/Recon.java
index 9ffe70bb7..9d15d21cb 100644
--- a/src/main/java/com/metaweb/gridworks/model/Recon.java
+++ b/src/main/java/com/metaweb/gridworks/model/Recon.java
@@ -82,8 +82,10 @@ public class Recon implements Serializable, HasFields, Jsonizable {
         if (candidates != null) {
             r.candidates = new ArrayList<ReconCandidate>(candidates);
         }
+        
         r.judgment = judgment;
         r.match = match;
+        
         return r;
     }
     
diff --git a/src/main/java/com/metaweb/gridworks/model/ReconStats.java b/src/main/java/com/metaweb/gridworks/model/ReconStats.java
index 58b131808..62238d064 100644
--- a/src/main/java/com/metaweb/gridworks/model/ReconStats.java
+++ b/src/main/java/com/metaweb/gridworks/model/ReconStats.java
@@ -15,7 +15,7 @@ import com.metaweb.gridworks.model.Recon.Judgment;
 public class ReconStats implements Serializable, Jsonizable {
     private static final long serialVersionUID = -4831409797104437854L;
 
-    static public ReconStats reconstruct(JSONObject obj) throws Exception {
+    static public ReconStats load(JSONObject obj) throws Exception {
         return new ReconStats(
                 obj.getInt("nonBlanks"),
                 obj.getInt("newTopics"),
diff --git a/src/main/java/com/metaweb/gridworks/model/Row.java b/src/main/java/com/metaweb/gridworks/model/Row.java
index 883b45dcb..70f1c45db 100644
--- a/src/main/java/com/metaweb/gridworks/model/Row.java
+++ b/src/main/java/com/metaweb/gridworks/model/Row.java
@@ -162,8 +162,10 @@ public class Row implements Serializable, HasFields, Jsonizable {
     }
     
     static public Row load(String s) throws Exception {
-        JSONObject obj = ParsingUtilities.evaluateJsonStringToObject(s);
-        
+        return s.length() == 0 ? null : load(ParsingUtilities.evaluateJsonStringToObject(s));
+    }
+    
+    static public Row load(JSONObject obj) throws Exception {
         JSONArray a = obj.getJSONArray("cells");
         int count = a.length();
         
diff --git a/src/main/java/com/metaweb/gridworks/model/changes/CellChange.java b/src/main/java/com/metaweb/gridworks/model/changes/CellChange.java
index 6968f643f..9f2de419b 100644
--- a/src/main/java/com/metaweb/gridworks/model/changes/CellChange.java
+++ b/src/main/java/com/metaweb/gridworks/model/changes/CellChange.java
@@ -66,9 +66,13 @@ public class CellChange implements Change {
             } else if ("cell".equals(field)) {
                 cellIndex = Integer.parseInt(value);
             } else if ("new".equals(field)) {
-                newCell = Cell.load(value);
+                if (value.length() > 0) {
+                    newCell = Cell.load(value);
+                }
             } else if ("old".equals(field)) {
-                oldCell = Cell.load(value);
+                if (value.length() > 0) {
+                    oldCell = Cell.load(value);
+                }
             }
         }
         
diff --git a/src/main/java/com/metaweb/gridworks/model/changes/ReconChange.java b/src/main/java/com/metaweb/gridworks/model/changes/ReconChange.java
index 8a56008ac..5dda51e3b 100644
--- a/src/main/java/com/metaweb/gridworks/model/changes/ReconChange.java
+++ b/src/main/java/com/metaweb/gridworks/model/changes/ReconChange.java
@@ -87,10 +87,30 @@ public class ReconChange extends MassCellChange {
     }
     
     public void save(Writer writer, Properties options) throws IOException {
-        writer.write("newReconConfig="); _newReconConfig.save(writer); writer.write('\n'); 
-        writer.write("newReconStats="); _newReconStats.save(writer); writer.write('\n'); 
-        writer.write("oldReconConfig="); _oldReconConfig.save(writer); writer.write('\n'); 
-        writer.write("oldReconStats="); _oldReconStats.save(writer); writer.write('\n'); 
+        writer.write("newReconConfig="); 
+        if (_newReconConfig != null) {
+            _newReconConfig.save(writer); 
+        }
+        writer.write('\n');
+        
+        writer.write("newReconStats=");
+        if (_newReconStats != null) {
+            _newReconStats.save(writer);
+        }
+        writer.write('\n');
+        
+        writer.write("oldReconConfig=");
+        if (_oldReconConfig != null) {
+            _oldReconConfig.save(writer); 
+        }
+        writer.write('\n');
+        
+        writer.write("oldReconStats=");
+        if (_oldReconStats != null) {
+            _oldReconStats.save(writer); 
+        }
+        writer.write('\n');
+        
         super.save(writer, options);
     }
     
@@ -111,13 +131,21 @@ public class ReconChange extends MassCellChange {
             String value = line.substring(equal + 1);
             
             if ("newReconConfig".equals(field)) {
-                newReconConfig = ReconConfig.reconstruct(ParsingUtilities.evaluateJsonStringToObject(value));
+                if (value.length() > 0) {
+                    newReconConfig = ReconConfig.reconstruct(ParsingUtilities.evaluateJsonStringToObject(value));
+                }
             } else if ("newReconStats".equals(field)) {
-                newReconStats = ReconStats.reconstruct(ParsingUtilities.evaluateJsonStringToObject(value));
+                if (value.length() > 0) {
+                    newReconStats = ReconStats.load(ParsingUtilities.evaluateJsonStringToObject(value));
+                }
             } else if ("oldReconConfig".equals(field)) {
-                oldReconConfig = ReconConfig.reconstruct(ParsingUtilities.evaluateJsonStringToObject(value));
+                if (value.length() > 0) {
+                    oldReconConfig = ReconConfig.reconstruct(ParsingUtilities.evaluateJsonStringToObject(value));
+                }
             } else if ("oldReconStats".equals(field)) {
-                oldReconStats = ReconStats.reconstruct(ParsingUtilities.evaluateJsonStringToObject(value));
+                if (value.length() > 0) {
+                    oldReconStats = ReconStats.load(ParsingUtilities.evaluateJsonStringToObject(value));
+                }
             } else if ("commonColumnName".equals(field)) {
                 commonColumnName = value;
             } else if ("cellChangeCount".equals(field)) {
diff --git a/src/main/java/com/metaweb/gridworks/operations/ReconDiscardJudgmentsOperation.java b/src/main/java/com/metaweb/gridworks/operations/ReconDiscardJudgmentsOperation.java
index 47b334b2d..a127c9698 100644
--- a/src/main/java/com/metaweb/gridworks/operations/ReconDiscardJudgmentsOperation.java
+++ b/src/main/java/com/metaweb/gridworks/operations/ReconDiscardJudgmentsOperation.java
@@ -72,17 +72,16 @@ public class ReconDiscardJudgmentsOperation extends EngineDependentMassCellOpera
             }
             
             public boolean visit(Project project, int rowIndex, Row row, boolean contextual) {
-                if (cellIndex < row.cells.size()) {
-                    Cell cell = row.cells.get(cellIndex);
-                    if (cell.recon != null) {
-                        Recon recon = cell.recon.dup();
-                        recon.judgment = Judgment.None;
-    
-                        Cell newCell = new Cell(cell.value, recon);
-                        
-                        CellChange cellChange = new CellChange(rowIndex, cellIndex, cell, newCell);
-                        cellChanges.add(cellChange);
-                    }
+                Cell cell = row.getCell(cellIndex);
+                if (cell != null && cell.recon != null) {
+                    Recon recon = cell.recon.dup();
+                    recon.judgment = Judgment.None;
+                    recon.match = null;
+
+                    Cell newCell = new Cell(cell.value, recon);
+                    
+                    CellChange cellChange = new CellChange(rowIndex, cellIndex, cell, newCell);
+                    cellChanges.add(cellChange);
                 }
                 return false;
             }