$\qed$
+\subsection{Tip Contents}
+
+We will consider some $D$ and prove the Exclusive Tip Contents form.
+We use the Coherence of $C$ as just proved.
+
+xxx the coherence is not that useful ?
+
+\subsubsection{For $L \in \py, D \in \py$:}
+
+xxx need to recheck this
+
+$C \in \py$ $C \haspatch P$ so $D \isin C \equiv D \le C$. OK.
+
+\subsubsection{For $L \in \py, D \not\in \py, R \in \py$:}
+
+Tip Contents for $L$: $D \isin L \equiv D \isin \baseof{L}$.
+
+Tip Contents for $R$: $D \isin R \equiv D \isin \baseof{R}$.
+
+But by Tip Merge, $\baseof{R} \ge \baseof{L}$
+
\end{document}