In the last 20 years that thinking has changed dramatically. Dinos are no longer regarded as dimwitted and clumsy. No one's saying a Triceratops could outrun a horse, but lately some scientists particularly Jack Horner think T. rex couldn't hunt.
They say it couldn't hunt because of its small forearms, the "fact" that it couldn't run any faster than 20 MPH due to there not being enough muscle on its legs and the fact that it had a great sense of smell, which is akin to a scavenger.
First the thing about it not being able to run is based on the idea that it must've been eight tons or more. But recent studies have shown that all the bones in its body except the legs were hollow. If that's the case, that would reduce its body weight by half or more, thus enabling it to run.
The argument about the forelimbs is just weak. The secretary bird of Africa doesn't have hands with which to hunt. It just uses its feet and beak to pick off snakes. So what's everyone's take?