Recently a fellow Prism rebreather diver took his rig to a "rebreather friendly" resort in the islands. During the course of the week a battery connection broke and he was unable to use his electronics. He had no problems with this and proceeded to start the dive with the unit turned off in manual mode. An Inspiration instructor who works with the resort stopped him and forbid him to dive. The Prism diver proceeded to explain that this was a safe practice with the Prism and that he was thoroughly trained in using the unit in this mode. The instructor still didnt allow him to dive and eventually contacted the Prism office and gave his opinion on how this was dangerous and a "fatality waiting to happen". As also a Prism diver, I can say that all students are thoroughly trained in the manual mode in various emergency situations. I only have 40 hours on my rig, but 35 of those hours are in the manual mode.The manual mode is a fairly simple process on the Prism. As long as a diver has a complete understanding of partial pressures(as all begining rebreather students should know) and a rig that has the capability to easily maintain a given pressure manually(regardless of what make rebreather it is) why was this diver stopped from diving? Is this the general concensus among Inspiration instructors??