Deter didn't work for us...haven't tried Forbid. I notice that there is a direct correlation with the poop eating and the frequency of treat giving.
The more that their diet is composed of treat foods, the more they eat their poop. Only give Sadie dog food for 2 days, she won't eat the poop. I wonder if she is smelling the treat in the poop and eating it to uh...savor the taste again?
Some people say you can use tabasco, but I'll be honest, Ritz and Sadie don't mind the taste.
The only GUARANTEED way to get rid of poop eating, is to pick it up as soon as you see it so they can't reinforce their own bad behavior by eating it and enjoying it. If the pills don't work, you can try spraying bitter apple on a piece of poop and leaving it around. This is the same principle as the pills though, so I'm not sure it will help.
Good luck, and if you find a solution, share it because I know there are a lot more puppies eating poop than owners willing to admit it =)
I have 2 of them.
-Nate