Humans are crafty sons of bitches. They hunted down mammoths...
Neanderthals were probably a lot smarter than we think as well not too mention a lot stronger.
I personally don't think cavemen behaved like half apes, homo sapiens have always been well homo sapiens, intellectually capable, they weren't dumber than people are now. Put a modern human on a deserted island with no modern tools and no knowledge of things he read in books and he is no different than a human being of 150 000 years ago, surviving on his wits, trial and error but by logical thinking.
You can easily resurrect a human of 200 000 years old and teach him how to drive a car.