Crackheads are candy coated coffee beans. A box of them contains 600mg of caffeine, roughly equivalent to 7.5 cans of Red Bull. I ate the box over about a 20 minute period.
Three hours later, I’m a bit jittery and need to pee. A lot. Thanks, diuretic effects. I don’t feel any more alert or awake though. I could probably go for a nap.
Thankfully, I am through my school years and have no need to stay up and cram for an exam. 
If I had eaten that, I would be shaking too much to type an OP. I would probably also be awke for then next few days.
My body has a caffeine fail. I drank one of those energy drinks mixed with alcohol and got sleepy. I give up.
I ate one coffee bean as an experiment, and it was awful. How would candy coating them help?
The sweet coating would take the edge off the bitterness. It wouldn’t help with the crunchy/gritty effect, though. I like chocolate covered coffee beans myself, but if I ate a whole container of them I would end up like that episode of “Futurama” where Fry drinks 100 cups of coffee and gets so cranked that time stops for him.
I’m thinking that in eating a coffee bean your body might not extract as much readily absorbable caffeine as grinding them up and puring boiling water over them.
I thinking you should wait to crap them out, then make coffee out of them!