First, some background:
I took Fundies almost half a year ago now, and have done about 50 dives since then. I was reasonably system-compatible going in, but certainly the class changed my diving, even having read a lot and spent two days with Bob (Sherwood) previously. During the class, though, I made a conscious decision not to give up my computer immediately but rather keep diving it in computer mode while I dove tables in my head, for a few reasons:
-Fundies preaches gauge use, but doesn't teach much if anything about the practical aspects of how to go about doing so (there are tables...but they weren't in the printed materials when I took the course, and they weren't taught, and tables are a pain to remember, etc.; there is ratio deco...but it's not taught at this level; and there's the rule of 120(air) and 130(Nitrox32), which appears nowhere in the printed materials, and is a bit hush hush, perhaps for liability reasons). It's rather like Helium in that respect (ask ScubaFeend how he feels about that one!).
-While I'm about as conservative about pushing limits as it gets, my OW training was hardcore Jersey (that's a positive, despite what some may think), and I still have the mindset of, "What if I get trapped in monofilament and am detained an extra 5 minutes?" Barring total catastrophic loss of my buddy's gas, I'd have plenty of gas to do any required deco, but I wouldn't know how much time I needed to spend doing it. A computer solves that. So would Ratio Deco, but again, not taught at this level.
-I sat down with the PADI NDL tables and compared them to the rule of 120, and found them to correspond pretty nicely, but I still didn't quite trust the thing. How good can it be when it's not written down anywhere?
Fast forward a few months (about 3 months ago), and I'm diving in 90fsw. Still diving rule of 130 (since I'm on Nitrox), with several minutes of MDL time to go. Computer decides I need 3 minutes of deco at 10 feet, but clears it by the time I reach 10 feet. Minorly annoying, but not a problem. It's a DiveRite Duo at SF2 (maximum conservatism). If it really bothered me I'd turn the SF down so it would be less conservative, but still act as a check.
Fast forward to this month, and I'm diving in 60fsw on air (ouch. Can I say that in this forum?
). Rule of 120 gives me another 8 minutes of MDL time. The computer decides at this point that I need 13 minutes of decompression...at 10 feet. Note this accumulated quite rapidly, since I noticed it at 3 minutes of decompression about three minutes prior, and had decided to ignore the computer since I was diving the rule of 120 and there was a simulated OOA situation which seemed more pressing.
Anyway, I'm done diving the computer as a computer. It's not the amount of deco (although given the OOA it became even clearer to me why more deco is not always better and that it's a balancing of risks), but that it wanted the entire 13 minutes at 10 feet. When I did a nice ascent at 30, then 20 for a while, then 10, it gave almost no credit for the 20 foot stop and penalized for the 30. If I really had racked up nearly the Rec3 course limit's worth of decompression, I'm quite sure I wouldn't want to do it all at 10 feet!
So if I had to do it over again, would I still keep the computer in computer mode post-Fundies? Yes. I think I learned a lot by making the transition pretty slow, and at very least I needed the crutch for a little while. But I think I've reached the point where it's more of a net risk than a net benefit.
Comments/criticisms welcome, as always.
Ari
I took Fundies almost half a year ago now, and have done about 50 dives since then. I was reasonably system-compatible going in, but certainly the class changed my diving, even having read a lot and spent two days with Bob (Sherwood) previously. During the class, though, I made a conscious decision not to give up my computer immediately but rather keep diving it in computer mode while I dove tables in my head, for a few reasons:
-Fundies preaches gauge use, but doesn't teach much if anything about the practical aspects of how to go about doing so (there are tables...but they weren't in the printed materials when I took the course, and they weren't taught, and tables are a pain to remember, etc.; there is ratio deco...but it's not taught at this level; and there's the rule of 120(air) and 130(Nitrox32), which appears nowhere in the printed materials, and is a bit hush hush, perhaps for liability reasons). It's rather like Helium in that respect (ask ScubaFeend how he feels about that one!).
-While I'm about as conservative about pushing limits as it gets, my OW training was hardcore Jersey (that's a positive, despite what some may think), and I still have the mindset of, "What if I get trapped in monofilament and am detained an extra 5 minutes?" Barring total catastrophic loss of my buddy's gas, I'd have plenty of gas to do any required deco, but I wouldn't know how much time I needed to spend doing it. A computer solves that. So would Ratio Deco, but again, not taught at this level.
-I sat down with the PADI NDL tables and compared them to the rule of 120, and found them to correspond pretty nicely, but I still didn't quite trust the thing. How good can it be when it's not written down anywhere?
Fast forward a few months (about 3 months ago), and I'm diving in 90fsw. Still diving rule of 130 (since I'm on Nitrox), with several minutes of MDL time to go. Computer decides I need 3 minutes of deco at 10 feet, but clears it by the time I reach 10 feet. Minorly annoying, but not a problem. It's a DiveRite Duo at SF2 (maximum conservatism). If it really bothered me I'd turn the SF down so it would be less conservative, but still act as a check.
Fast forward to this month, and I'm diving in 60fsw on air (ouch. Can I say that in this forum?
). Rule of 120 gives me another 8 minutes of MDL time. The computer decides at this point that I need 13 minutes of decompression...at 10 feet. Note this accumulated quite rapidly, since I noticed it at 3 minutes of decompression about three minutes prior, and had decided to ignore the computer since I was diving the rule of 120 and there was a simulated OOA situation which seemed more pressing.Anyway, I'm done diving the computer as a computer. It's not the amount of deco (although given the OOA it became even clearer to me why more deco is not always better and that it's a balancing of risks), but that it wanted the entire 13 minutes at 10 feet. When I did a nice ascent at 30, then 20 for a while, then 10, it gave almost no credit for the 20 foot stop and penalized for the 30. If I really had racked up nearly the Rec3 course limit's worth of decompression, I'm quite sure I wouldn't want to do it all at 10 feet!
So if I had to do it over again, would I still keep the computer in computer mode post-Fundies? Yes. I think I learned a lot by making the transition pretty slow, and at very least I needed the crutch for a little while. But I think I've reached the point where it's more of a net risk than a net benefit.
Comments/criticisms welcome, as always.
Ari
. Occasionally I would forget to put my Aeris into Gauge Mode and it would display a bunch of information I didn't really need and/or trust (Air Time Remaining: 3 hours+ when using my HP100 doubles on a shallow training dive) and just get in my way. But one time I left it in computer mode, on air, for a Nitrox32 dive with around a 70-foot avg depth and it was just happy with me. 
