The wire bond or "bridge" is a TINY piece of wire which will burn out under over voltage conditions. Also, the reflector cup and semiconductor well will oxidize under over voltage conditions.
It will "burn up" instead of having a filament to break like a standard incandecent bulb.
Diodes are one-way electrical gates, LED's are one-way electrical gates which emit light while power is flowing the correct way. AC systems flow power backwards and forwards so the LED will only emit light during the "forward" time. Trying to use an LED on a non-rectified system will result in voltage spikes, flickering, poor lighting, and burned out LED's.
The diodes used to rectify AC voltage to DC voltage are heat sinked and rated at the stated full wattage of the system (usually stated as a amperage rating). In the case of the ricky stator regulator/rectifier, it's rated 15 amps at 12VDC.
Using an LED for a headlight (not a low power tailight or indicator light) on a poorly regulated AC circuit like the lighting circuit on the blaster will result in a lot of replacement parts, poor lighting in general, and a bunch of making back out of the woods in the dark.
If you want to run high power LED high lighting system, you need to do a DC conversion with a battery buffer system. It's the only way to get consistent, bright, low power consumption lighting.
The other choice is a DC conversion and an HID system but it takes more power. Usually about 25-30 watts running power and 50-60 watts startup power which means you can only run one bulb (MAYBE two but it would be close to discharging the battery the whole time it was running) consistantly.