Oh, what the hell...
fishhunta:
Why does my bladder have to be black???
I believe mine is blue, actually. If you're asking why you can't use red bungee wings, the issue there is with the bungee wings, not the red color.
Why can't I dive a steel single?
You can. I have no idea where this misconception comes from.
What is wrong with my full foot fins?
DIR fins need to be stiff non-split fins that you can easily do frog kicks, helicopter kicks and back kicks with. The requirement is that you be able to do the kicks in the fins, not that the fins need to be any particular type -- although in practice jetfins and turtles have the best design for this kind of propulsion.
And you might be surprised at how much being able to back up improves your diving.
Why must I wear a drysuit with steel tanks?
With single steels it isn't a requirement. With double steels, a wing failure, and a wetsuit that compresses with depth you could wind up 20-35# or more negative and plastered on the bottom with nothing ditchable.
Why must I use trimix past 100ft??
Narcosis, gas breathing difficulty, CO2 build-up, and weight. GUE is really geared towards creating technical divers who are expected to be diving in caves or overheads where the risk of taking a CO2 hit needs to be eliminated. In clear warm water on NDL dives where you can always ascend directly to 80 fsw to clear your head out, this may seem like overkill.