Hatchrite

Does anyone here use Hatchrite?
I have a bag I'd like to use if/when I get some eggs. I was reading through the instructions and I'm wondering why it says not to add any water. Does it really already have enough water in it for the entire incubator period?
For those of you who have used it, did you put a hole in your egg box like it recommends?

I'm using it, but my girl is really late so I haven't put any eggs on it yet. It is wet, but I'm not buying that it was wet enough for the entire incubation. My bag at least, when I squeezed the hatchrite none of it stayed together. I was told that if it started to get too dry during incubation put a tsp of water in the corners and let it disburse itself. I added a tiny bit of water so that it stayed together at least a little bit when I squeezed it.

I put no holes in the box. I Just open to allow air exchange every few days. But the moisture has held up for me for the duration of incubation.

If your container isn't sealed well then hatchrite tends to dry out quickly and needs to have water added to it to keep up the humidity.
I didn't care for it after using it last year, so I switched to the substrateless method this year :)

This is the third year I've used it and haven't had any issues other than adding a little water last year. It's better to have to add a little water than have it too wet...