In 2014, December 6th and 7th were a Saturday and Sunday, respectively. So if you were there last year from 12/5 - 12/8, it would have included that weekend. That weekend was a perfect storm of Candlelight Ceremony crowds, Raver Day crowds and attendees of the nearby pharmacy convention who were staying at the DLR hotels and other nearby hotels. Some people say it was more crowded than they remember ever seeing
Disneyland before. Fortunately, this year Raver Day is being held on the weekend after Candlelight, and the pharmacy convention is in New Orleans, I think. So the crowds should be manageable enough.
The Christmas Parade is happening this year, to some extent (that much is official), but it may only be a daytime thing. No one knows yet. So I don't know if it will have an impact on crowds. For all we know, Disney may take it and throw it into a surprise hard ticket party!