He probably referring to the *number* of bags loaded, not the loaders speed.
The issue has been discussed other times on the forum in the past: it's not possible to increase the number of bags, because of how animations works in FSX and how they can be coordinated and how much memory they take (the longer they are, the more memory they take), we might theoretically increase the number of carts, but this would create a lot of problems with limited space in the apron for the vehicle to maneuver, especially with 3rd party sceneries that have static ground objects that can't be moved away.
So no, you can't have more bags loaded.