Hey Mike,
I had the same thought when I started making Solomon Bars, but I quickly found out they didn't work quite like I expected. I did put together something else that could be unraveled much more quickly though. (Of course, I?m sure others thought of it before me

)
I don't have my ABOK with me, so I don't know the exact name of the macram? I'm thinking of, but it's something along the lines of a Banister Bar, but using only one strand of rope. You can tie half hitches down a line, resulting in a spiral, or, if you want it to sit better on your wrist, you can force the half-hitches to line up in a straight line or alternate them, so they look like half of a Solomon Bar. This way, you can pull the whole thing apart at one time, (of course, I personally prefer the look of the Solomon Bar, but this one is much quicker to untie.) My camera's out of juice, but I'll pick up some batteries tonight so I can show you what I'm talking about.
PS. JD of TIAT has an awesome video about tying a Slat's Rescue Belt that can be untied all at once too.
Thanks,
Son of Liberty