H2Ohm, I think that it is sage advice to not share computers. IF I were an instructor, I'd certainly teach that to my students. Just as a physician, I give health advice that is more conservative than what I might practice in my own life. However in this case, my buddy and I had the same number of dives; his profiles were slightly more aggressive than mine had been on our 3 previous dives together. So his computer had a bit more nitrogen loading than mine and our final dive was a relatively shallow (by NC standards) 60 foot dive with no deco. I knew that I was being ultra cautious with my deco on my first dive of that day, as I did more than twice what was required for the nitrox mix I was diving (though still not enough for 21% as the computer was calculating the dive). The issue in my mind was whether to stay in the water an extra 10 minutes hanging on the line and inconvenience the 20 folks on the boat in order to satisfy the computer, though I knew I had done way more than enough deco at that point. I had plenty of air but decided it wasn't right to make every one else keep waiting, at this point my dive time was at 68 minutes. But again, I agree with your advice to not share computers and not ignore your own computer and would not advocate any others follow my example on this dive. In the end though it was a great dive.