For the future:
You can test the polarity of any Led with one CR123 cell or 2xAA cells (max.3 Volts)
You can, but with Seouls, there's an inbuilt static-protection diode. It's a Zener, which means that with reverse voltages above ~0.6V, a lot of current can flow.
I didn't realise the diode was there until I checked the reverse-voltage current draw of one of my caving lamps. With the Luxeon-based units it was insignificant, but with SSCs attached to identical driving electronics, it was a couple of amps, being somewhat limited by the path through the electronics.
From playing around, direct application of a 3xNiMH pack to a Seoul with reverse connection seems to blow the protection diode open about half the time, but turns it into a 2-way short circuit the other half of the time, making the LED useless.