Hi friends !!
What about RRS-49 or Class rule C2.2 Crew Positioning ???

I can't see any competitor with any part of their torsos outside the lifelines.

The lower torso of “green jacket” is outside the lifelines. Remember, the hips attach to the torso.

Case 36

Torso: the torso or trunk is an anatomical term for the central part or core of many animal bodies (including humans) from which extend the neck and limbs. The torso includes: the thoracic segment of the trunk, the abdominal segment of the trunk, and the perineum.

The perineum is generally defined as the surface region in both males and females between the pubic symphysis and the coccyx. The perineum is below the pelvic diaphragm and between the legs.

So basically .. imagine a babies 'onesie' with cut-off sleeves ..

Case 36

Helps how?

John, I think the illustrations do help to visualize how the line is drawn up (and down) from the lifeline.

The best part of the OP’s picture  is that the person in the green spray top is the helmsman!  Now that's talent! :-)

So, now I think that the person in the green spray top breach rule 49.2.

The line is not from the lifeline, must be drawn up from the top of the "post".....no ?

From Case 36 (the origin of the drawing) .. "... an imaginary line projected vertically from the top of the lifelines".  It's a simplified drawing and the line is intended to be from the lifeline as shown.