diff --git a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/FullDataFileHandler.java b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/FullDataFileHandler.java
index 81ec52f95..010314c36 100644
--- a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/FullDataFileHandler.java
+++ b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/FullDataFileHandler.java
@@ -248,8 +248,9 @@ public class FullDataFileHandler implements IFullDataSourceProvider
 			return null;
 		}
 		
-		// This is a CAS with expected null value.
 		this.topDetailLevel.updateAndGet(oldDetailLevel -> Math.max(oldDetailLevel, pos.sectionDetailLevel));
+		
+		// This is a CAS with expected null value.
 		FullDataMetaFile metaFileCas = this.fileBySectionPos.putIfAbsent(pos, metaFile);
 		return metaFileCas == null ? metaFile : metaFileCas;
     }
@@ -266,6 +267,7 @@ public class FullDataFileHandler implements IFullDataSourceProvider
         byte sectionDetail = posAreaToGet.sectionDetailLevel;
         boolean allEmpty = true;
 		
+		// get all existing files for this position
         outerLoop:
         while (--sectionDetail >= this.minDetailLevel)
 		{
@@ -439,28 +441,33 @@ public class FullDataFileHandler implements IFullDataSourceProvider
 				HighDetailIncompleteFullDataSource.createEmpty(pos) : 
 				LowDetailIncompleteFullDataSource.createEmpty(pos);
 	}
-
-	protected CompletableFuture<IIncompleteFullDataSource> sampleFromFiles(IIncompleteFullDataSource source, ArrayList<FullDataMetaFile> existingFiles)
+	
+	/** populates the given data source using the given array of files */
+	protected CompletableFuture<IIncompleteFullDataSource> sampleFromFileArray(IIncompleteFullDataSource recipientFullDataSource, ArrayList<FullDataMetaFile> existingFiles)
 	{
 		// read in the existing data
 		final ArrayList<CompletableFuture<Void>> loadDataFutures = new ArrayList<>(existingFiles.size());
 		for (FullDataMetaFile existingFile : existingFiles)
 		{
 			loadDataFutures.add(existingFile.loadOrGetCachedDataSourceAsync()
-					.exceptionally((ex) -> /*Ignore file read errors*/null)
-					.thenAccept((fullDataSource) ->
+				.exceptionally((ex) -> /*Ignore file read errors*/null)
+				.thenAccept((existingFullDataSource) ->
+				{
+					if (existingFullDataSource == null)
 					{
-						if (fullDataSource == null) return;
-						//this.checkIfSectionNeedsAdditionalGeneration(pos, fullDataSource);
-						//LOGGER.info("Merging data from {} into {}", data.getSectionPos(), pos);
-						source.sampleFrom(fullDataSource);
-					})
+						return;
+					}
+					
+					//LOGGER.info("Merging data from {} into {}", data.getSectionPos(), pos);
+					recipientFullDataSource.sampleFrom(existingFullDataSource);
+				})
 			);
 		}
-		return CompletableFuture.allOf(loadDataFutures.toArray(new CompletableFuture[0])).thenApply(v -> source);
+		return CompletableFuture.allOf(loadDataFutures.toArray(new CompletableFuture[0])).thenApply(voidObj -> recipientFullDataSource);
 	}
 
-	protected void makeFiles(ArrayList<DhSectionPos> posList, ArrayList<FullDataMetaFile> output) {
+	protected void makeFiles(ArrayList<DhSectionPos> posList, ArrayList<FullDataMetaFile> output)
+	{
 		for (DhSectionPos missingPos : posList)
 		{
 			FullDataMetaFile newFile = this.getLoadOrMakeFile(missingPos, true);
@@ -487,8 +494,8 @@ public class FullDataFileHandler implements IFullDataSourceProvider
         }
 		else
 		{
-			makeFiles(missing, existFiles);
-			return sampleFromFiles(source, existFiles).thenApply(IIncompleteFullDataSource::tryPromotingToCompleteDataSource)
+			this.makeFiles(missing, existFiles);
+			return this.sampleFromFileArray(source, existFiles).thenApply(IIncompleteFullDataSource::tryPromotingToCompleteDataSource)
 				.exceptionally((e) ->
 				{
 					FullDataMetaFile newMetaFile = this.removeCorruptedFile(pos, file, e);
diff --git a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/GeneratedFullDataFileHandler.java b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/GeneratedFullDataFileHandler.java
index dd315783b..5e9c3d96e 100644
--- a/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/GeneratedFullDataFileHandler.java
+++ b/core/src/main/java/com/seibel/distanthorizons/core/file/fullDatafile/GeneratedFullDataFileHandler.java
@@ -120,7 +120,7 @@ public class GeneratedFullDataFileHandler extends FullDataFileHandler
 				ArrayList<FullDataMetaFile> existingFiles = new ArrayList<>();
 				byte sectDetailLevel = (byte) (DhSectionPos.SECTION_MINIMUM_DETAIL_LEVEL + maxSectDataDetailLevel);
 				pos.forEachChildAtLevel(sectDetailLevel, p -> existingFiles.add(getLoadOrMakeFile(p, true)));
-				return sampleFromFiles(dataSource, existingFiles).thenApply(this::tryPromoteDataSource)
+				return sampleFromFileArray(dataSource, existingFiles).thenApply(this::tryPromoteDataSource)
 						.exceptionally((e) ->
 						{
 							FullDataMetaFile newMetaFile = removeCorruptedFile(pos, file, e);
@@ -152,26 +152,28 @@ public class GeneratedFullDataFileHandler extends FullDataFileHandler
 
 	// Try update the gen queue on this data source. If null, then nothing was done.
 	@Nullable
-	private CompletableFuture<IFullDataSource> updateDataGenStatus(FullDataMetaFile file, IIncompleteFullDataSource data)
+	private CompletableFuture<IFullDataSource> updateFromExistingDataSources(FullDataMetaFile file, IIncompleteFullDataSource data)
 	{
 		DhSectionPos pos = file.pos;
 		ArrayList<FullDataMetaFile> existingFiles = new ArrayList<>();
 		ArrayList<DhSectionPos> missingPositions = new ArrayList<>();
 		this.getDataFilesForPosition(pos, pos, existingFiles, missingPositions);
-
-		if (missingPositions.size() == 1) {
+		
+		if (missingPositions.size() == 1)
+		{
 			// Only missing myself. I.e. no child file data exists yet.
-			return tryStartGenTask(file, data);
+			return this.tryStartGenTask(file, data);
 		}
-		else {
-			// Has stuff to sample.
-			makeFiles(missingPositions, existingFiles);
-			return sampleFromFiles(data, existingFiles).thenApply(this::tryPromoteDataSource)
-				.exceptionally((e) ->
-				{
-					FullDataMetaFile newMetaFile = removeCorruptedFile(pos, file, e);
-					return null;
-				});
+		else
+		{
+			// There are other data source files to sample from.
+			this.makeFiles(missingPositions, existingFiles);
+			return this.sampleFromFileArray(data, existingFiles).thenApply(this::tryPromoteDataSource)
+					.exceptionally((e) ->
+					{
+						this.removeCorruptedFile(pos, file, e);
+						return null;
+					});
 		}
 	}
 
@@ -179,8 +181,8 @@ public class GeneratedFullDataFileHandler extends FullDataFileHandler
 	public CompletableFuture<IFullDataSource> onCreateDataFile(FullDataMetaFile file)
 	{
 		DhSectionPos pos = file.pos;
-		CompletableFuture<IFullDataSource> future = updateDataGenStatus(file, data);
 		IIncompleteFullDataSource data = makeEmptyDataSource(pos);
+		CompletableFuture<IFullDataSource> future = updateFromExistingDataSources(file, data);
 		// Cant start gen task, so return the data
 		return future == null ? CompletableFuture.completedFuture(data) : future;
 	}
@@ -205,12 +207,16 @@ public class GeneratedFullDataFileHandler extends FullDataFileHandler
 		}
 		this.fireOnGenPosSuccessListeners(source.getSectionPos());
 
-		if (source instanceof IIncompleteFullDataSource && !file.genQueueChecked) {
+		if (source instanceof IIncompleteFullDataSource && !file.genQueueChecked)
+		{
 			WorldGenerationQueue worldGenQueue = this.worldGenQueueRef.get();
-			if (worldGenQueue != null) {
-				CompletableFuture<IFullDataSource> future = updateDataGenStatus(file, (IIncompleteFullDataSource) source);
-				if (future != null) {
-					return future.thenApply((newSource) -> {
+			if (worldGenQueue != null)
+			{
+				CompletableFuture<IFullDataSource> future = this.updateFromExistingDataSources(file, (IIncompleteFullDataSource) source);
+				if (future != null)
+				{
+					return future.thenApply((newSource) ->
+					{
 						onUpdated.accept(newSource);
 						return newSource;
 					});