That just makes your writes to the disk more efficient because of block alignment and caching nonsense.
This is not true. The reason to use dd is to be able to write a fixed amount from any location in the source to any location in the destination. You have lots of control how this happens. But the way everyone uses it, to write a whole file to another whole file it offers no benefit. If anything you have to tune the prams to get decent performance out of it. Any other copy tool uses a better block size by default and so all you can do is match the performance of other copy commands like bash redirection and cp.