You're right, Jim.
There are actually capacitors specially made to withstand the sudden arc-ing connection to a battery. The automotive people use them, but I don't know about any rated for a 40-Volt arc. What we need is a two-stage connector. As you plug in, you wipe against the resistor-limited path, then through into the hard connection. That will limit the time and opportunity for bumping the throttle while in the current-limited path. So do you figure 100-Ohms is enough current limitinng? I'll try it myself, and let you know.
Dean Pappas