- Are drivers really that important?
It depends. Drivers are useful in terms of efficiency, and longivity / thermal management. But they are not absolutely necessary in all situations.
1A. Wouldn't it be somewhat of a benefit running it without a driver, but with a good heatsink, to make it even brighter, sort of like overclocking a computer?
heatsinking doesn't fundamentally solve the problem. Drivers are necessary / desirable because they solve a very important problem: LED's forward voltage drop goes down with temperature and a little change in voltage can generate tremendous amount of change in current. So a little bit of heat reduces Vfwd. That leads to more current -> more power dissipation from the led -> higher led temperature -> even lower Vfwd -> ...
[quot]1B. Even if life is reduced a bit, is it as big of a deal as people say? [/quote]
Your reasoning is sound.
Can anyone help explain why these numbers aren't adding up?
Too many possibilities: your battery may not be delivering the voltage specified to generate the current, etc.