Big Pond :
In your assumed 5 acre pond what are the goals for it and what predator fish or fishes would you want. With that info a better risk assessment can be made. Both crappie and GG , like all pond mgt. tools have a proper place ( here very limited) and risks and rewards. The difference in the 2 for risk mgt. purposes is crappie have a known risk factor while the risk factor for GG is much more of an unknown.
Like ML I don't plan to use either in a pond with a diverse fish mix and never with other non-bass sunfish (BG, RE etc.). Now if all you care about are big blues and flatheads then as long as you have enough forage of the right size I am not sure it makes a difference.

ewest