∃∃U1. ⦃G1, L1⦄ ⊢ T1 ➡*[h, g] U1 & T1 = U1 → ⊥ & ⦃G1, L1, U1⦄ ≥[h, g] ⦃G2, L2, U2⦄.
#h #g #G1 #G2 #L1 #L2 #T1 #T2 #H #U2 #HTU2 #HnTU2 elim (fpbs_fpbsa … H) -H
#L0 #T0 #HT10 #H10 #HL02 elim (eq_term_dec T1 T0) [ -HT10 | -HnTU2 ]
-[ #H destruct lapply (lpxs_cpxs_trans … HTU2 … HL02) -HTU2
- #HTU2 elim (fqus_cpxs_trans_neq … H10 … HTU2 HnTU2) -T2
- /3 width=6 by fqus_lpxs_fpbs, ex3_intro/
-| /4 width=6 by fpbs_cpxs_trans, fqus_lpxs_fpbs, ex3_intro/
+[ #H destruct lapply (llpxs_cpxs_trans … HTU2 … HL02)
+ #H elim (fqus_cpxs_trans_neq … H10 … H HnTU2) -H10 -H -HnTU2
+ /4 width=8 by fqus_llpxs_fpbs, llpxs_cpxs_conf_dx, ex3_intro/
+| /4 width=6 by fpbs_cpxs_trans, fqus_llpxs_fpbs, ex3_intro/
]
qed-.