lemma lsubr_cpx_trans: ∀h,G. lsub_trans … (cpx h G) lsubr.
#h #G #L1 #T1 #T2 * /3 width=4 by lsubr_cpg_trans, ex_intro/
qed-.
+
+lemma cpx_bind_unit: ∀h,L,G,V1,V2. ⦃G, L⦄ ⊢ V1 ⬈[h] V2 →
+ ∀J,T1,T2. ⦃G, L.ⓤ{J}⦄ ⊢ T1 ⬈[h] T2 →
+ ∀p,I. ⦃G, L⦄ ⊢ ⓑ{p,I}V1.T1 ⬈[h] ⓑ{p,I}V2.T2.
+/4 width=4 by lsubr_cpx_trans, cpx_bind, lsubr_unit/ qed.
+