diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index 4a2ed49776f67..118e3b4d7781f 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,7 +1,5 @@
 *SVN*
 
-* Improve associations performance by avoiding named block arguments.  #11109 [adymo]
-
 * Ensure that modifying has_and_belongs_to_many actions clear the query cache.  Closes #10840 [john.andrews]
 
 * Fix issue where Table#references doesn't pass a :null option to a *_type attribute for polymorphic associations.  Closes #10753 [railsjitsu]
diff --git a/activerecord/lib/active_record/associations/association_collection.rb b/activerecord/lib/active_record/associations/association_collection.rb
index d400a5c772abe..79cd227c0c59d 100644
--- a/activerecord/lib/active_record/associations/association_collection.rb
+++ b/activerecord/lib/active_record/associations/association_collection.rb
@@ -43,8 +43,8 @@ def delete_all
       end
 
       # Calculate sum using SQL, not Enumerable
-      def sum(*args)
-        calculate(:sum, *args) { |*block_args| yield(*block_args) if block_given? }
+      def sum(*args, &block)
+        calculate(:sum, *args, &block)
       end
 
       # Remove +records+ from this association.  Does not destroy +records+.
@@ -121,9 +121,9 @@ def empty?
         size.zero?
       end
 
-      def any?
+      def any?(&block)
         if block_given?
-          method_missing(:any?) { |*block_args| yield(*block_args) if block_given? }
+          method_missing(:any?, &block)
         else
           !empty?
         end
@@ -157,13 +157,11 @@ def replace(other_array)
 
 
       protected
-        def method_missing(method, *args)
+        def method_missing(method, *args, &block)
           if @target.respond_to?(method) || (!@reflection.klass.respond_to?(method) && Class.respond_to?(method))
-            super { |*block_args| yield(*block_args) if block_given? }
+            super
           else
-            @reflection.klass.send(:with_scope, construct_scope) {
-                @reflection.klass.send(method, *args) { |*block_args| yield(*block_args) if block_given? }
-            }
+            @reflection.klass.send(:with_scope, construct_scope) { @reflection.klass.send(method, *args, &block) }
           end
         end
 
@@ -189,15 +187,15 @@ def find_target
 
       private
 
-        def create_record(attrs)
+        def create_record(attrs, &block)
           ensure_owner_is_not_new
           record = @reflection.klass.send(:with_scope, :create => construct_scope[:create]) { @reflection.klass.new(attrs) }
-          add_record_to_target_with_callbacks(record) { |*block_args| yield(*block_args) if block_given? }
+          add_record_to_target_with_callbacks(record, &block)
         end
 
-        def build_record(attrs)
+        def build_record(attrs, &block)
           record = @reflection.klass.new(attrs)
-          add_record_to_target_with_callbacks(record) { |*block_args| yield(*block_args) if block_given? }
+          add_record_to_target_with_callbacks(record, &block)
         end
 
         def add_record_to_target_with_callbacks(record)
diff --git a/activerecord/lib/active_record/associations/association_proxy.rb b/activerecord/lib/active_record/associations/association_proxy.rb
index 16a2943c76df9..ed1dd36f75290 100644
--- a/activerecord/lib/active_record/associations/association_proxy.rb
+++ b/activerecord/lib/active_record/associations/association_proxy.rb
@@ -78,12 +78,6 @@ def inspect
         @target.inspect
       end
 
-      def to_xml(options={}, &block)
-        if load_target
-          @target.to_xml(options, &block)
-        end
-      end
-
       protected
         def dependent?
           @reflection.options[:dependent]
@@ -126,9 +120,9 @@ def merge_options_from_reflection!(options)
         end
 
       private
-        def method_missing(method, *args)
+        def method_missing(method, *args, &block)
           if load_target
-            @target.send(method, *args)  { |*block_args| yield(*block_args) if block_given? }
+            @target.send(method, *args, &block)
           end
         end
 
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 85bc86443f36d..883375707d9e3 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -113,8 +113,8 @@ def size
       end
 
       # Calculate sum using SQL, not Enumerable
-      def sum(*args)
-        calculate(:sum, *args) { |*block_args| yield(*block_args) if block_given? }
+      def sum(*args, &block)
+        calculate(:sum, *args, &block)
       end
       
       def count(*args)
@@ -128,13 +128,11 @@ def count(*args)
       end
 
       protected
-        def method_missing(method, *args)
+        def method_missing(method, *args, &block)
           if @target.respond_to?(method) || (!@reflection.klass.respond_to?(method) && Class.respond_to?(method))
-            super { |*block_args| yield(*block_args) if block_given? }
+            super
           else
-            @reflection.klass.send(:with_scope, construct_scope) {
-                @reflection.klass.send(method, *args) { |*block_args| yield(*block_args) if block_given? }
-            }
+            @reflection.klass.send(:with_scope, construct_scope) { @reflection.klass.send(method, *args, &block) }
           end
         end