I think the biggest advantage of high heat, is that when you screw it up, you've only wasted 6 hours of your life instead of 12 hours.
Since we know it's possible to produce very tender and juicy brisket in a 350 degree oven, it makes sense that a tender brisket in a high heat smoker should be possible also. Like kickass said, the hardest part is timing. The window between undercooked and overcooked is much smaller at high heat.
“If you don’t know who I am, then maybe your best course would be to tread lightly.”
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