Yikes, thats pretty bad.

Here's a sample from the stock lens. Using only available light... ND2, F4, subject (about 2.3 meters) away. Rack focus on the gun. No color correction

http://www.nick-p.com/JVC.jpg

Did a quick test today to witness Tim's point by myself.
This breathing is indeed a major problem, at least for my kind of filmmaking. I hardly ever have zooms in my films but a lot of intricate rack focusing (done with 35mm primes and P&S so far).
But I need a handy solution for theatrical docu work.
Tried the P&S with a Cooke zoom, but that's totally unwieldy !
Tim, if I were to use the JVC adapter and a top Nikkor or Canon zoom (assuming that the mounts can be matched) would that be a cost-effective solution ? Or with the P&S re-maufactured primes ?
Are there any other practical workarounds with the 16x ?
Thanks, guys !

macro focus is all I can think of.

Can you be more specific, Mark?

Correction: the P&S lenses are of course not zooms, silly of me