"......if it is set up right."

Exactly ! Thank you, Phantom3D.

Allow me to quote myself from from this thread over at DAZ:
http://forum.daz3d.com/viewtopic.php?t=137495&postdays=0&postorder=asc&start=120

People are mixing up several things:

1. DEFAULT (UNSCALED) Kids-4 bend in all versions of Poser without breaking.
   NOONE said otherwise, and that is NOT the problem..
   (Their strange "Mini-Me" default body shape is whole different can of worms)

2. "Single axis scaling" DOES work in Poser IF the figure is properly rigged according to Poser standards.
   It DOES not matter WHAT RIGGING TOOLS are used for the rigging.
   What matters is the RIGGING METHOD that was used.
   Was it rigged ADHERING to POSER'S STANDARDS or not, NOT was it rigged using POSER'S or STUDIO'S rigging tools.

3. CONFORMING a "single axis scaled" CLOTHING ITEM does ONLY work in PoserPro 2010.
   (In older versions the clothing reverts to default 100% scale when conformed)
   BUT ONLY if the "single axis scaling" in BOTH the figure AS WELL as the CLOTHING was set up using POSER'S STANDARDS for "single axis scaling".

If it isn't, the mesh and clothing will still break. <<

And just to be clear:
I'm definitly NOT in favor of single axis scaling.

Didn't like Apollo's ADS, don't like DAZ "morphforms".

A dedicated rig is a much better solution than a "one size fits all" setup, because a rig is more than just joint centers.
Even if you just morph a mesh from "emacicated" to "heavy", the falloff zones and JCM's will cause problems unless you re-adjust them.
Scaling also distorts limbs in a way that isn't realistic, even if the scaling is propery set up.

But the point is, IF one insists to make a figure highly "scaleable", doing it in Poser is NOT a problem.