I was researching this topic and found this very informative article. This is also a great website for info on certain pedals (compression, EQ, generally). Enjoy!
Isolated Power Supply Versus Daisy Chain
PART 1
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Is the power supply making my pedal chain noisy?
Maybe you are...
Apparently, they needed a way to solve the 18v power consumption of most of their pedals, which resulted in this nice piece of gear. Now on sale for 33% off as Musician's Friend's Stupid Deal of the Day...