It is true, isn't it, that the Skywalker connection did not exist in ANH, right?
I mean, it's certainly not particularly evident. It's one reason why I've never given much shrift to the notion that the reveal in ESB is one of the greatest twists in cinema history, because it's just so out of left field. There's a gun on the mantle.
Maybe it's just been too long since I've seen the OT, but I don't recall any clues.
Yes, that's also why Obi-wan Kenboi is then shifted into being a bit of a liar.. Vader is just the henchman of the week.