The chum wasn't too finely ground - and you don't want it that way. You don't want a slick - you want chum. Down here they mix the chum with oats and sand to make the balls. That way, when as the ball goes down, it dissolves, and the chum particles (along with the sand and the oats) come off of the ball and the yellowtail eat them.
Heck, when I was cleaning my fish, I found a ton of the oats and chum in their stomachs.
I have never heard of anyone using this technique outside of the Florida Keys, but I don't see why it couldn't work elsewhere. I have a cousin who lives in Mobile and I have fished there many times (which is similar to fishing any of the gulf states like Texas and Louisiana - the gulf waters are shallow compared to here.)
I must say that mixing these "ingredients" is quite messy, but well worth it. The boats down here get a big clothes basket and pour the ingredients and "blend" them in there. I would say that you could probably make anywhere between 50 to 100 balls. Just make sure that you compact the balls and make them VERY TIGHT. You want the balls to be quite most, then squeeze them tight. Then wrap your line around the ball about 5 to 15 times depending on the depth. This way, the wraps keep the ball more intact and it goes down deeper. In the Gulf, where the water is about 60 feet, you really shouldn't need any more than 5 wraps or so, and the balls don't need to be big.
Make sure that you also have a bucket of water to wash your hand after you make the ball and through it in the water.
Try it out and tell me how you do. Remember, use small hooks and small baits - not too big - maybe a little more than the size of the hook.
Zachary