diff --git a/lib/Rewrite/DeltaTree.cpp b/lib/Rewrite/DeltaTree.cpp
index dd096c2..f771531 100644
--- a/lib/Rewrite/DeltaTree.cpp
+++ b/lib/Rewrite/DeltaTree.cpp
@@ -58,10 +58,12 @@
 } // end anonymous namespace
 
 
-struct InsertResult {
-  DeltaTreeNode *LHS, *RHS;
-  SourceDelta Split;
-};
+namespace {
+  struct InsertResult {
+    DeltaTreeNode *LHS, *RHS;
+    SourceDelta Split;
+  };
+} // end anonymous namespace
 
 
 namespace {
@@ -72,8 +74,8 @@
     
     /// WidthFactor - This controls the number of K/V slots held in the BTree:
     /// how wide it is.  Each level of the BTree is guaranteed to have at least
-    /// WidthFactor-1 K/V pairs (unless the whole tree is less full than that)
-    /// and may have at most 2*WidthFactor-1 K/V pairs.
+    /// WidthFactor-1 K/V pairs (except the root) and may have at most
+    /// 2*WidthFactor-1 K/V pairs.
     enum { WidthFactor = 8 };
     
     /// Values - This tracks the SourceDelta's currently in this node.
diff --git a/lib/Rewrite/Rewriter.cpp b/lib/Rewrite/Rewriter.cpp
index 1c1903c..f7dcdd2 100644
--- a/lib/Rewrite/Rewriter.cpp
+++ b/lib/Rewrite/Rewriter.cpp
@@ -27,8 +27,12 @@
   assert(RealOffset+Size < Buffer.size() && "Invalid location");
   
   // Remove the dead characters.
+#ifdef USE_ROPE_VECTOR
   RewriteRope::iterator I = Buffer.getAtOffset(RealOffset);
   Buffer.erase(I, I+Size);
+#else
+  Buffer.erase(RealOffset, Size);
+#endif
 
   // Add a delta so that future changes are offset correctly.
   AddDelta(OrigOffset, -Size);
@@ -40,23 +44,29 @@
   
   // Nothing to insert, exit early.
   if (StrLen == 0) return;
-  
+
   unsigned RealOffset = getMappedOffset(OrigOffset, InsertAfter);
+
+#ifdef USE_ROPE_VECTOR
   assert(RealOffset <= Buffer.size() && "Invalid location");
 
   // Insert the new characters.
   Buffer.insert(Buffer.getAtOffset(RealOffset), StrData, StrData+StrLen);
+#else
+  Buffer.insert(RealOffset, StrData, StrData+StrLen);
+#endif
   
   // Add a delta so that future changes are offset correctly.
   AddDelta(OrigOffset, StrLen);
 }
 
 /// ReplaceText - This method replaces a range of characters in the input
-/// buffer with a new string.  This is effectively a combined "remove/insert"
+/// buffer with a new string.  This is effectively a combined "remove+insert"
 /// operation.
 void RewriteBuffer::ReplaceText(unsigned OrigOffset, unsigned OrigLength,
                                 const char *NewStr, unsigned NewLength) {
   unsigned RealOffset = getMappedOffset(OrigOffset, true);
+#ifdef USE_ROPE_VECTOR
   assert(RealOffset+OrigLength <= Buffer.size() && "Invalid location");
 
   // Overwrite the common piece.
@@ -76,7 +86,12 @@
     RewriteRope::iterator I = Buffer.getAtOffset(RealOffset+NewLength);
     Buffer.erase(I, I+(OrigLength-NewLength));
   }
-  AddDelta(OrigOffset, NewLength-OrigLength);
+#else
+  Buffer.erase(RealOffset, OrigLength);
+  Buffer.insert(RealOffset, NewStr, NewStr+NewLength);
+#endif
+  if (OrigLength != NewLength)
+    AddDelta(OrigOffset, NewLength-OrigLength);
 }