diff --git a/interp/baker/__init__.py b/interp/baker/__init__.py
index e2bb5e9..9dc01fb 100644
--- a/interp/baker/__init__.py
+++ b/interp/baker/__init__.py
@@ -205,6 +205,10 @@ def _samples_ur(items, k, offset = 0):
     yield tuple([x + offset  for sel in selections for x in sel])
 
 def memoize(f):
+  """
+    I only cache on power and phicount; I figure that one should stick to a
+    particular offset throughout one's codebase.
+  """
   cache = {}
   def memf(*x, **kargs):
     if x not in cache: