Originally Posted by BurtonAvenger
It's going to help absorb micro vibrations which go right to your feet and on upward into your knees. Sounds more like you're locking your knees up instead of bending with the force of the pow.
I doubt hes "locking his knees" when hes riding through choppy pow because that would make it impossible to balance I think he just wants to make riding through choppy pow less tiring.
think of you riding at high speeds as a damped driven harmonic oscillator (can be solved by ordinary differential equations) this means that there is a force driving the oscillatory motion (vibrations) a damping constant (something resisting the driving force) and then theres the normal frequency associated with the system (the frequency that if you were to drive at the amplitude of the wave would just keep adding (think of spinning a jump rope the only way you can keep it going is by swinging your arm at the normal frequency of the jump rope system)) every system of a board / rider will have a damping term because there is something there resisting the driver, all a dampening system does is increase the damping coefficient. It turns out that the natural frequency of the system is dynamic (which means it changes with how you ride (basically because you and the board are not perfectly rigid you dont have a single normal frequency so will never experience vibrations building on your natural frequency)), but what increasing the damping constant does is just take more energy away from each oscillation which leaves you with a smoother ride. So a board with a damping system (larger damping coefficient) will damp more energy out of you riding through choppy pow but since the force's acting on you when you do charge through some tracked down pow are so large the difference between a board with a damping system and without will be unnoticeable.
to make riding though choppy pow less tiring you want a deck that is going transfer more of your momentum over the lump of pow rather than down into it. if you have a flexy board a larger component of your momentum will be directed downward for a longer period of time because your board will bend before it starts to "float" over the lump of pow. The longer your momentum tis directed not over the lump of powder the more momentum you lose which means more stress is put on your body (because of conservation of energy the energy from you not floating of the lump of pow will have to go some where and it turns out that it gets transferred into you via you obsorbing the impact). This all translates to you need a stiffer deck that will flex less when you come uppon some choppy pow.