Succeeds despite the over-acting

Rating: 8/10 (27 July 2011)

I see Back to the Future has grossed $350 million. I wonder how much it would have made if I had directed it?
While Michael J. Fox and Christopher Lloyd deliver impeccable performances, and it is impossible to imagine the movie without them, most of the rest of the acting is pretty bad, sometimes way, way over the top, such as the 1985 revised apologetic Biff. Anywhere else, audiences would have cringed. I cringe every time I see it.
But you can't argue with success. Did the movie succeed because of the over-acting, or despite it? Perhaps teenagers were amused by the silliness. But for adults, the movie is strong enough that they seemingly overlook it.
Back to the Future has many strengths, such as drawing you into the fantasy of what it would be like to travel back to the 1950s. There is enough detail and authenticity to the recreation that you are able to imagine you have gone back in time with the movie. I like movies that get young people interested in understanding what it was like before they were born. Yet, if you are going to go through all the trouble of recreating the 1950s, the time-travel fantasy effect would work better if the acting were more believable.
On the other hand, they overdo the sin-city decay of the 1985 present, for a small American town/city. There are some echoes of Bedford Falls without George Bailey, from It's a Wonderful Life (which would make a nice companion viewing). And speaking of connections, I believe this is the same town set used in Harvey with James Stewart, and for Hitchcock's Shadow of a Doubt (?).
The bottom line is Back to the Future starts with a cute concept and gives it several layers of action and irony that keep you amused. It succeeds in the rare accomplishment for a comedy of working just about as effectively upon subsequent viewings. This is because the humor is not based on crude jokes or bad language, but on the manipulation of the tension in the awkward, off-balance relationships between the characters. Part of the genius of this film is the way these awkward relationships are resolved to the audience's immense satisfaction.
These strengths are why I still enjoy this film, despite the over- acting. But producer Steven Spielberg is certainly no fool, especially when it comes to hitting the bulls-eye with younger viewers. So I must assume this is what he was aiming for. What do you think?