Was it ever established that Vader even remembered his previous life as Anakin Skywalker?
ETA - nevermind. Vader recognized Obi Wan when he met him on the Death Star,
So we’re putting spoilers right in the thread title now? Sheesh!
For a 40 year old movie?
Some of us are still working our way through the series. I’m only up to the holiday special.
‘The Force told me to do it this way.’ Could that help get around it? Be it Yoda or Obi-Wan: upon clearing one’s mind and meditating tall buildings in a single bound, would he calmly say something philosophical before offering up a shrug and going with the flow?
Bwahahahahahaha! That’s an hour of your life you’ll never get back.
But the empire was scouring the galaxy for former Jedi to exterminate as part of the Great Jedi Purge. You’d think old Ben Kenobi would be an obvious tell to those imperial inquisitors. Unless “Kenobi” was as common as “Smith” in the Empire 
.
Imperial Inquisitor #1: “Hey do you think any of these old Jedi might be trying to hide out under their real names? They seem like a pretty unimaginative bunch. Howabout that Obi-Wan Kenobi guy that cut off Lord Vader’s legs? Think we should do a database search? Or even just send a flyer to the planetary governors and local constabularies? ‘Be on the lookout’ and all that? Twenty million quatloo award for information leading to extermination maybe?”
II #2: “What!? Not even the Jedi were that stupid. And we don’t have the discretionary funds for rewards! Death Stars don’t just build themselves you know. Besides there must be 80 million Kenobis in the gamma quadrant alone. Where would we even start?”
II #1 "Yeah, I guess you’re right."
Ever stop and think how that all-powerful “Force” must have been pure BS, since Vader didn’t even recognize his own children until the second movie?
Vader didn’t know he had any living children.
As far as the galaxy’s-most-adept-force-user not being able to detect them, well, that’s a different story…
I can’t speak for Yoda, but I read the first book when it was published, and it was obvious that “Darth Vader” = “Dark Father,” so I certainly didn’t find it unexpected.
Maybe so, but I like how Alec Guinness gets a shifty, evasive expression when Luke asks “How did my father die?” Obi-Wan looks like he’s thinking, “Oh, shit, I wish he hadn’t asked me that. Well, I hope he buys this bullshit story I’m about to feed him.” It may not have been planned that way, but it works.
Personally, if I had been Vader, I would have told Luke IMMEDIATELY. No lengthy lightsaber duel, and no cutting Luke’s hand off and cornering him over a bottomless pit. The moment he showed up in Cloud City, I’d say, “I’m your father. Let’s go have a beer and talk about it. I have a proposition that may interest you—how does ruling the galaxy as father and son sound?” Then, if Luke says no, freeze him and ship him off to the Emperor. That wouldn’t have made for a very exciting third act, though.
Apparently when they were filming, there were only three people who knew about the big reveal—George Lucas, James Earl Jones, and Mark Hamill. While they were filming, the line was “Obi Wan killed your father.” It wasn’t changed to the voiceover “I am your father” until later and it was a big sworn secret. Maybe a couple other crew members knew. This is according to Mark Hamill.
I like to point out when people say “you can’t spoil a X-year-old movie/TV show” that, just as the XKCD comic noted, there are always younger people coming up in the pipeline who have not yet experienced the thing in question.
Everything about the prequel trilogy was stupid. There’s simply no getting around it; those stories didn’t even make sense within themselves. All three movies are full of logical idiocies and plot holes you could fit the Death Star into.
It was a joke. Maybe there’s an XKCD comic for that…
Similarly, when Han gives the “twelve parsecs” line, Obi-Wan has an eye-roll that seems to say "Yeah, right, and next you’re going to send us out for a bucket of turboprop wash, right?
Similarly, in the “What a piece of junk!”…“I made a lot of special modifications myself” exchange, Obi-Wan is giving a massive eye-roll when Han delivers that last line. (Which, full disclosure, I had never even noticed in over 40 years; I only now see it because someone pointed it out in the comments section for that YouTube video.)
Luke is a teenager - he’s going hear “Confront” as “Fight” - and he already wanted to kill Vader for several reasons.
If Obi-wan was going to stay on the same planet as Luke why didn’t he just raise him himself and train him the whole time?
Diapers? Is even the Force powerful enough to battle the evil that an infant excretes daily?