That's the whole idea: minimize, or in the case of the Totems, eliminate the leverage. Cuz leverage is bad, at least that's how Camhead and I understand what rgold has said on the subject. I don't personally have anything to add one way or another; just pointing out the design feature of the Totems.
In the first case, the downward load on the stem produces an outward force on the cam which is a fraction of the total load, so it would take a lot to extract the cam. I know of some rigid-stem placements that were made in flaring horizontals in the Gunks BITD that might not hold at all with today's flexible stems.
In the second case, a flexible stem loads the cams almost perpendicular to their expansion plane, nearly nullifying the mechanical principles that make a cam work. The rigid stem provides torque that gives the cams a chance to expand against the crack walls.