diff --git a/rules/game_process.tex b/rules/game_process.tex
index 6e82ee6..3a60907 100644
--- a/rules/game_process.tex
+++ b/rules/game_process.tex
@@ -67,8 +67,9 @@ \subsection{Robot States}
   \centerline{\includegraphics[width=0.9\columnwidth]{figs/states_new.pdf}}
   \caption{Diagram of the robot states.
     \\\textbf{Chest button} transitions are shown as gray arrows.
-    However, any transition possible should be sent by the GameController.
     \\\textbf{GameController} transitions are shown as black arrows.
+    % The following sentence is necessary because the GameController can undo actions.
+    However, any transition possible can actually be sent by the GameController.
     \\Calibration transitions are shown as purple arrows which mean pressing the \textbf{front head button + the chest button}.
     \\From any state it can be transitioned to the \texttt{unstiff} state, shown as a blue arrow, via pressing all \textbf{three head buttons}.
     Pressing the \textbf{chest button} in the \texttt{unstiff} state allows a transition to the \texttt{initial} state, or a state as indicated by the GameController.}