FD,
Wheel landings. Fast taxying (which is a requirement for being able to do wheel landings consistently and safely). Wheel landings. Cross-wind landings. Wheel landings. Slipping (using full rudder, while turning - not just a little bit of rudder to lose 50' on final). Wheel landings. Flying airliner-size circuits. Generally flying like an airliner, for example my lack of willingness to use full aileron deflection.
Basically, apart from the fact I hadn't been taught wheel landings, the main issue was that I was flying the Cub like a PA28 with the third wheel in the back. The Cub is a very different beast, and although it's quite happy to be flown the way that students are taught to fly PA28s, to restrict yourself to this style of flying prevents you from taking full advantage of the aircraft. And having the skill to fly it properly could well get you out of trouble in a cross-wind (and made some of the landings I did look easy, when I certainly would have ground-looped had I tried them without that training).
FFF
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PS - The training must have worked. When I got a few hours on the club's Aztec a month or so later, my instructor accused me of trying to fly the Aztec like a Cub - quite a change from being accused of flying the Cub like a 747!!!