We give the precise correspondence between polarized linear logic and polarized classical logic. The properties of focalization and reversion of linear proofs citeAndrPar,lc,lktq are at the heart of our analysis: we show that the tq-protocol of normalization for the classical systems LKe and LKer perfectly fits normalization of polarized proof-nets. In section refisos, some more semantical considerations allow to recover LC as a reinement of multiplicative LKe