The moving over, under, or through a stunt, pyramid, individual, or prop rules, collectively referred to as the “Over/Under” rules, are only applicable when passing over or under a torso. They do not apply to only passing over arms or legs. This means you can punch front over a leg without violating this rule. The tumbling restrictions regarding Over/Under are the same for all levels, including Level 6, stating:
Tumbling over, under, or through a stunt, individual, or prop, is not allowed.
The stunt and pyramid restrictions differ by level, and don’t exist for Level 5.
No stunt, pyramid, or individual may move over or under another separate stunt, pyramid or individual. – Levels 1-3
No stunt or pyramid may move over or under another separate stunt or pyramid. – Level 4
Levels 1-3 can’t move Over/Under anything separate, but Level 4 can move Over/Under a separate individual. Please note use of the word “Separate” in the rules above because that is what makes some skills, leap frogs being an example, possible. A leap frog stunt passes over a torso, but since the top person is connected to the person they pass over, it’s not a separate stunt or individual so the rule doesn’t apply. The same concept applies to leap frog pyramids in higher levels.