For this one, I tip my hat to the terrific stand-up comedian Ed Byrne, who actually raised this point as part of one of his earlier tours.

The conundrum is this: you tend to remember the people who brought you together in life. You’d certainly remember the person who played Johnny B Goode in such dramatic fashion at the Enchantment Under The Sea dance. And, given that Lorraine had such a crush on Marty in 1955, she’s unlikely to have forgotten him altogether.

So then, why, when Marty gets back to 1985, do George or Lorraine seem to have no recognition of his pivotal part in their lives? Wouldn’t, when Marty gets to the age of 13 or 14, one of them think that something a bit odd was happening, in that they’ve managed to breed someone who looks exactly like the person who brought them together all those years ago?

Even appreciating that they didn’t know ‘Calvin Klein’ for long, his impact upon them was such that they’d still have an idea what he looks like, many years later.

You can find Ed’s DVD where he talks about this right here.