Back in 1983-84 when he did his Star Licks bit he mentions that you need seperate amps for seperate effects, that if you didn't things would just mash together and sound aweful..
so NOW in 2006 he authorises the DIGITECH team to relase a pedal in HIS name that has multiple effects in the same pedal.. and you DONT need seperate amps for them.. what gives?
ok.. NOW I will open this for flaming.. I mean discussion..
He was right back then, and frankly it still holds true now, for the best quality you should run separate amps, however with today's digital effects you get a much cleaner sound than you did before and you can get away with it.
But if you were to do it properly in a professional studio you would still try to separate it as much as possible.
In star licks he's referring to multiple amps to keep the delay signals seperate (one for the original signal and another two - each for it's own delay signal).
The delay patch on the Digitech simulates three amplifiers being used in this way. There is no contradiction.
The Digitech pedal in effect has the amp(s) inside it as a digital model. There is no need for any real guitar amp with the pedal. You can plug it straight into your soundcard or similar to get the full Vox amp sound.
It's a legitimate question-anyone who hammers you for this probably was just waiting for a chance to pounce. The previous answers are all correct-in the simplest terms-the technolgy just got better over the past 20 + years. For some one as intelligent and as technically proficient as Brian, I would imagine that he gets inspired by the new inventions that have been made and will continue to be made in the future. His use of echo which took so many years to "perfect", can now be done by any knucklehead with a guitar, an amp and about $1200.