diff --git a/bonobo/execution/contexts/node.py b/bonobo/execution/contexts/node.py
index 767b929..a18f4d7 100644
--- a/bonobo/execution/contexts/node.py
+++ b/bonobo/execution/contexts/node.py
@@ -1,5 +1,6 @@
 import logging
 import sys
+import warnings
 from queue import Empty
 from time import sleep
 from types import GeneratorType
@@ -27,7 +28,7 @@ class NodeExecutionContext(WithStatistics, LoopingExecutionContext):
 
     def __init__(self, wrapped, parent=None, services=None, _input=None, _outputs=None):
         LoopingExecutionContext.__init__(self, wrapped, parent=parent, services=services)
-        WithStatistics.__init__(self, 'in', 'out', 'err')
+        WithStatistics.__init__(self, 'in', 'out', 'err', 'warn')
 
         self.input = _input or Input()
         self.outputs = _outputs or []
@@ -125,19 +126,8 @@ class NodeExecutionContext(WithStatistics, LoopingExecutionContext):
 
         input_bag = self.get()
 
-        # todo add timer
-        self.handle_results(input_bag, input_bag.apply(self._stack))
+        results = input_bag.apply(self._stack)
 
-    def kill(self):
-        if not self.started:
-            raise RuntimeError('Cannot kill a node context that has not started yet.')
-
-        if self.stopped:
-            raise RuntimeError('Cannot kill a node context that has already stopped.')
-
-        self._killed = True
-
-    def handle_results(self, input_bag, results):
         # self._exec_time += timer.duration
         # Put data onto output channels
 
@@ -159,6 +149,15 @@ class NodeExecutionContext(WithStatistics, LoopingExecutionContext):
             # self._exec_count += 1
             pass
 
+    def kill(self):
+        if not self.started:
+            raise RuntimeError('Cannot kill a node context that has not started yet.')
+
+        if self.stopped:
+            raise RuntimeError('Cannot kill a node context that has already stopped.')
+
+        self._killed = True
+
     def as_dict(self):
         return {
             'status': self.status,
@@ -169,7 +168,7 @@ class NodeExecutionContext(WithStatistics, LoopingExecutionContext):
 
 
 def isflag(param):
-    return isinstance(param, Token) and param in (NOT_MODIFIED, )
+    return isinstance(param, Token) and param in (NOT_MODIFIED,)
 
 
 def split_tokens(output):
@@ -181,11 +180,11 @@ def split_tokens(output):
     """
     if isinstance(output, Token):
         # just a flag
-        return (output, ), ()
+        return (output,), ()
 
     if not istuple(output):
         # no flag
-        return (), (output, )
+        return (), (output,)
 
     i = 0
     while isflag(output[i]):
diff --git a/bonobo/nodes/io/csv.py b/bonobo/nodes/io/csv.py
index 6f24df6..c846a5f 100644
--- a/bonobo/nodes/io/csv.py
+++ b/bonobo/nodes/io/csv.py
@@ -61,12 +61,9 @@ class CsvReader(FileReader, CsvHandler):
             for _ in range(0, self.skip):
                 next(reader)
 
-        for row in reader:
+        for lineno, row in enumerate(reader):
             if len(row) != field_count:
-                warnings.warn('Got a line with %d fields, expecting %d.' % (
-                    len(row),
-                    field_count,
-                ))
+                warnings.warn('Got %d fields on line #%d, expecting %d.' % (len(row), lineno, field_count,))
 
             yield dict(zip(_headers, row))
 
diff --git a/bonobo/util/statistics.py b/bonobo/util/statistics.py
index 2f9c5c2..31da8b9 100644
--- a/bonobo/util/statistics.py
+++ b/bonobo/util/statistics.py
@@ -28,8 +28,8 @@ class WithStatistics:
         stats = tuple('{0}={1}'.format(name, cnt) for name, cnt in self.get_statistics(*args, **kwargs) if cnt > 0)
         return (kwargs.get('prefix', '') + ' '.join(stats)) if len(stats) else ''
 
-    def increment(self, name):
-        self.statistics[name] += 1
+    def increment(self, name, *, amount=1):
+        self.statistics[name] += amount
 
 
 class Timer: