There's an argument (and I think a good one) that in structured programming there should be only one return per function. It's not that hard -- you just have a variable and you set it to what you want to return and the last line of the function returns that variable. I think that some things Wirth did with Oberon, particularly in the post Oberon-OS versions like Oberon-07, are a bit restrictive, but they are always in the service of making code easier to read, even if it makes it slightly harder to write.

Show me significant concepts implemented in today's languages which cannot directly be traced back to "things that were important in 1960-s" or seventies ;-)