diff --git a/tantri/dipoles/__init__.py b/tantri/dipoles/__init__.py
index c4dbba5..8e864f2 100755
--- a/tantri/dipoles/__init__.py
+++ b/tantri/dipoles/__init__.py
@@ -31,6 +31,9 @@ class Dipole:
 	w: float
 
 	# For caching purposes tell each dipole where the dots are
+	# TODO: This can be done better by only passing into the time series the non-repeated p s and w,
+	#     and then creating a new wrapper type to include all the cached stuff.
+	#     Realistically, the dot positions and measurement type data should live in the time series.
 	dot_positions: typing.Sequence[DotPosition]
 
 	measurement_type: DipoleMeasurementType