Actually, the bearing is pulled into the hub using its' outer diameter as the point of applied force. Then with the bearing installed and the clip in its place the hub is installed into the center of the bearing. To do this the screw acts on the hub's outer edge and the bearing's inner diameter. That is the only way the interference fit between the hub and the bearing inner diameter can be accomplished without destroying the bearing itself. If it is attempted the other way around the actual bearings between the outer and inner races/diameters of the bearing's shell will have force applied to them and will fail. This is precisely why the bearing is destroyed when the hub is pulled from the wheel carrier, the bearing's inner diameter/race seperates from the outer diameter/race. When pulling the hub with a slide hammer be prepared for a struggle as the bearing takes quite a bit of force to come apart sometimes. Once apart part of the inner diameter/race will likely be stuck on the hub's inner part, this is most easily removed by grinding it almost through and then using a cold chisel to break the last bit. Early wheel carrier installation used some adhesive and may need a judicious heat applied to soften this up to allow the bearing's outer shell remainder to be pulled/pushed from it. Good luck!

Here's a short video showing the process using the SIR B90-M tool:

http://www.youtube.com/watch?v=vxcRUKYsTG0