-lemma req_cpx_trans (h) (G): req_transitive (cpx h G).
-#h #G #L2 #T1 #T2 #H @(cpx_ind … H) -G -L2 -T1 -T2 /2 width=2 by cpx_ess/
+lemma req_cpx_trans (G): req_transitive (cpx G).
+#G #L2 #T1 #T2 #H @(cpx_ind … H) -G -L2 -T1 -T2 /2 width=2 by cpx_qu/