You can crack them open ONLY if they are far enough along. I do different things.
I pinch to see if they crack on their own. (early in harvesting season)
When I'm tired of checking pods every day (late in harvesting season) I take them if I think they are far enough along and crack open myself. Some pods seem to never want to open on their own. I've had some that I know were more than 60 days along but were green as can be with no signs of being ready anytime soon so I took them and the seeds were ready. I've only had a couple that actually weren't ready out of about 1000.
Once you've done this for a little while you'll know when you can and when you cannot do something.
