Here is an interesting note from the datasheet on the dimmer that I just found from Lutron's site which notes that magnetic transformers need be used to feed transformer based systems (note that I'm using the Ariadni style dimmer):
Important Notes
1. CAUTION: Use "AY-" or "TG-" models only with permanentlyinstalled
120V incandescent or halogen fixtures. To avoid
overheating and possible damage to other equipment, do not use
to control receptacles, fluorescent lighting fixtures, motor-driven
appliances, or transformer-supplied appliances. Use "AYLV-"
models only with core and coil (magnetic) low-voltage
transformers. To control solid state (electronic) low-voltage
transformers, use Lutron electronic low-voltage dimmers.
