What is the benefit to using multiple RED rocket cards? Could someone please explain to me when it might be necessary to use multiple RED rocket cards in the same computer?  Does an additional card significantly improve workflow speeds for lower resolution video (such as 1080p), or is an additional card only useful 2k, 4k, etc?
The RedRocket card provides encoder and decoder support via specialized hardware that can do particular calculations well.  Having multiple cards doubles the amount of calculations that can be done.  Since at least some of the calculations can be done in parallel, having multiple cards increases the amount of processing power available.  It probably wouldn't be much of an additional advantage after hitting real time, but could probably allow for better scrubbing.