Ok. So you have a chicken. You kill it, you gut it, etc. you then go to cook it. Are you going to pull it off the grill early or are you going to wait until it is cooked thoroughly. It is basically the same thing that is going on here.
If it's the first time you're cooking chicken, you'll have to have a look at it every so often, see if it's done already. Same applies to the mod pack. You'll need to test it, see if it's stable.