Originally Posted by
Soma_Evan
It's been my experience with other frames such as the specialized langster, that having polished plates on the inside of the dropouts prevents the axle from getting adequate bite and can cause the wheel to slip under heavy torque. If you only ride around flat areas, or use brakes this is probably not a big problem, but if you are skidding down steep hills you really don't want your rear wheel moving around.
I've never had the wheel slip on either my Kagero or my Dodici Gara, both of which have double-sided stainless inserts.
The only time I ever had a wheel slip forward was when using a Phil Wood hub on my Leader 725 - mainly due to the Phil Wood axle hardware. I switched hubs and my wheel never slipped again. If axles aren't slipping all over the place on a steel frame, they're not going to be slipping on an aluminum frame with steel inserts.
I've seen some bikes with single-sided dropous get chewed up pretty bad and unfortunately, not everyone knows how to properly tighten their axle nuts to prevent such damage.