/3 width=6 by shnv_inv_snv, snv_lref/
]
| #a #I #G #L2 #V #T #_ #_ #IHV #IHT #L1 #HL12 destruct
/4 width=1 by snv_bind, lsubsv_pair/
/3 width=6 by shnv_inv_snv, snv_lref/
]
| #a #I #G #L2 #V #T #_ #_ #IHV #IHT #L1 #HL12 destruct
/4 width=1 by snv_bind, lsubsv_pair/