No, the PCD started out as a dance troupe of no-name video/backup dancers. They auditioned one night at Depp's
Viper Room and he was so impressed that he gave them their own regular night. As a result, the group gained its cache and celebrity chicks became interested. That's when Carmen Electra got involved and became the de facto "leader" of the pack for several years. Christina Applegate was another regular, but Christina Aguilera and a bunch of other Hollywood starlets all participated at one time or another.
As the PCD gained in status, they expanded from the
Viper Room and became interested in singing as a result of Gwen Stefani guesting with them. That's when the music company became involved. The PCD lineup was gutted (totally, as far as I can tell) and replaced with better looking chicks and a lead singer (Nicole) who could actually sing. The other girls do sing on the record, but they're reduced to the backup "Ewws" and "Ahhs" rather than any substantial singing parts. At this point, the PCD really became an entirely different entity based off the concept of the previous PCD group.
So really, there were three eras. First, the original PCD group who were a pseudo-burlesque dance troupe of unknowns. Then it morphed into the second PCD group that had Carmen Electra, Christina Applegate, and a variety of other celebrity guests. Then it morphed again into the current incarnation that has become pop stars.
And yes, I now know
far too much about the PCD.