I think they don't understand what's going on when you press the hub in. You support the inner cone/inner race, which pushes on the outer cone's inner race. No more force than is normally encountered when the bearing is fully assembled is put on the rollers as the clearances are set by the dimensions of the two inner races.
Sounds to me like they are doing it wrong, and then changed their approach to do it wrong another way instead of learning and understanding the right way to do it.
I am doing it the way the factory service manual outlines using the SST made by Kent-Moore. Though I use a Hub Tamer by OTC. Same tool just different branding and 1/10th the price.
Follow the directions Subaru gives. Some OE engineering is a compromise (mpg vs power vs emissions) but the basics (how to install a bearing) are not.