Since learning the sideways universe was really a waiting room for the afterlife, my dad asked me an interesting question about Sayid shooting Ben in the 1970s. Shouldn't he have remembered Sayid when he posed as Henry Gale? We understand that Ben getting shot and healed "took away his innocence" as described by Richard, the it seems looking back at the series overall that Ben would have had a reaction to seeing Sayid when locked up.