OK I'll have to try holding the button in a little (ok - a lot -) longer and wait for the chime. If that doesn't work, I may take up Andre's offer for the No-ESP black-box or resort to cutting in to the wiring and installing a master ESP shut-off switch a-la what Charger owners have resorted to doing...

The partial disable mode allows you to get some wheel-spin for what Dodge consideres necessary wheel spin for "sand" or light snow, according to the owners manual. But too much wheel spin will engage the ESP/Traction control. Also, I think fish-tailing may also still engage the ESP/traction control even when partially disabled.