What do you mean by "STEP"? IF I understand correctly, you may mean a wing LE that is either curved/bent ala Spitfire (elliptical) to the rear, or the wing's outer 1/3 or so that is actually smaller in chord.

In either case, the designer reduced tip chord for two reasons: it becomes elementary to reduce LE radius at the tip. It becomes elementary to reduce wing area at the tip. Both conditions allow a simpler set-up for snaps and spins that doesn't take more than 11-12 degrees of elevator to be effective.

My wing solution (that I've used the past 15 years or so) is simpler, just as effective if not more so, and is far easier to actually build. I simply choose to use a root chord to tip chord ratio that is fairly high by Pattern standards. Ratios of 3+ (18" root,6" tip) work very well in Pattern plus they bring the MAC closer to the fuse CL. (One current wing I'm using actually is closer to 21" root to 6" tip, or a 3 1/2 : 1 ratio). This wing type is bothered less by crosswind turbulence to boot, eventhough span is a full 2 meters.