diff --git a/src/shimmers/sketches/cilia_phase.cljs b/src/shimmers/sketches/cilia_phase.cljs
index da60e4dd..2a38b0fd 100644
--- a/src/shimmers/sketches/cilia_phase.cljs
+++ b/src/shimmers/sketches/cilia_phase.cljs
@@ -81,6 +81,7 @@
            length-fx cilia-amp rot-fx phase]}]
   (for [x samples]
     (let [pt (screen-space (:fn line-fx) x phase)
+          ;; what happens if the lookahead distance for the derivitive is oscillating?
           pt' (screen-space (:fn line-fx) (+ x 0.0001) phase)
           angle (+ (g/heading (tm/- pt' pt)) (* eq/TAU 0.25) ((:fn rot-fx) x))
           len (* height (+ cilia-amp (* cilia-amp ((:fn length-fx) x))))]