On home-build rebreathers. I seem to recall Pete referring to his home-build RB as 'the widow-maker'. It may have been tongue-in-cheek, or not

A RB is a task-orientated device. If you dont need it (or cant justify it), then is using one worth the greater risks involved?? That is just a question Im throwing in there for interest. Im not personally of the variety of diver who thinks RB divers are all going to die, I just dont personally feel the time/money/risk/requirements equation works for me. If it does for you, cool.
RBs do have some definite advantages in some applications, especially photography, as well as others like cheap mix (compared to oc mix), easier to support expeditions, the warmth factor, (and many others). I can also understand the allure, I like interesting shiny toys too

I believe mCCR's with constant mass flow have quite stable loops under normal workloads. But even given that, I dont think I would ever consider diving with 1 faulty PPO2 sensor out of 3. And I dont know if I would consider less than 3 to really be a viable option either.
For starters, if one is dodgy, its quite possible that one of the others is suspect too, if they are all the same age and run-time. Secondly, when you only have 2 sensors, you lose your 'voting logic'. Which of the two is correct??
Yes, if you have the capability, you can run diluent over the sensors and make a call as to which sensor to run off of. But in a task-loaded situation, are you going to read the right one? This is the sort of 'little thing' which can turn into a 'big thing' if the brown stuff hits the fan. IMHO, sweat the little things, and the big ones just tend to sort themselves out.
I guess to me that this sort of thing is more of a discipline question than anything else. A lack of discipline, and taking short-cuts, with RB's appears to be a really good way of needlessly putting yourself in harms way. If you take are willing to dive with known failures, then what's the problem with a missed pre-breathe? And from there on down the slippery slope of 'she'll be right'.
Packhorse. That was a generalized comment, NOT aimed at you, or in any way implying that you are un-disciplined, more just me generally musing and being philosophical, as I am often am at 1am (especially if Ive had a bourban or 2)
