Well -- Tara never does get her memories of that All the Way argument back, so in that sense it's "permanent." But she of course finds out about it -- and I don't think there's really any information that she's lost, in the way that Buffy completely loses that day of her life (and spends the next year of her life with Riley, the human version of Angel). With Connor, I think it's even worse. First of all, the new Connor that gets created ("They were supposed to fix that," Angel mentioned about wanting Connor to be rid of his attraction to older women, in Origin) really is a whole new identity -- he's not really "Connor" the guy we've seen in all the previous episodes, but a new person entirely. Second, he wipes crucial experiences from his friends' memories. Third, he completely alters the lives of Connor's new family without their consent. Fourth -- when he refuses to let the Orlon window be smashed, he also is risking his son's life, to preserve the illusion of his healthy life. Now -- I do see the other side to it. I think Angel is genuinely trying to do what he thinks is best; and on some level, he is giving Connor the life that he, Angel, wishes he could have -- it's almost noble in a way. But it's nobility that is all associated with the idea that Angel knows better than anyone else.