So I'm playing through System Shock 2 for the second time, with the first time being many years ago. I decided to try going the Psi route as it seemed the more interesting route with lots of different possible playstyles. However, the game really isn't very good at explaining to me the specifics of the various skills (or my reading comprehension is not up to snuff). So I had a couple questions maybe you helpful lot could help me with.

When a skill's description says: "duration: 10 seconds + 5 seconds per PSI", does 'PSI' mean "my PSI stat", or "the number of Psi Points I use (by choosing to charge or not charge)"?

That leads me to my second question: I just don't really understand charging Psi Skills. I know if you charge to the square it uses 2 Psi Points instead of one, but with the Cryokinesis I don't notice any discernible difference in damage or effect. In fact I don't notice any additional affect with most other skills that I have used so far. Maybe It's more subtle and my more modern gaming brain is too used to things being called out in bold text so I just don't notice. Another example is the "reduce alarm" skill; whether I charge it or not, it seems to reduce about 20 seconds on the alarm per use.

Also if you have any other helpful psi-related information, I would love to hear it as it will make my life much easier during this playthrough.

For those interested, I really am enjoying this build so far, it's a very different and presents unique challenges from most games I've played, even those that are spiritually trying to tap into the SS2 genre.

EDIT: Maybe this shouldn't have been a "Question Post", but it doesn't seem like I can change that.