No this is not that case. Let us assume that CIO opened two application parcel, on 5th feb, 2015, one is CC and other is DD and they found both are complete in all respects. They will simply charge CC and issue it file number and UCI number and for the DD they will also issue the file number and UCI number and send the DD through their postal service to the bank for encashment. The applicant who had CC will immediatley see the result in his CC statement but DD person although his file has also been considered and gotton File number as well UC number on the same day as CC person, but he will see result of encashment at later stage and it may range from 3-10 days depending on the banks involved in the DD. So, timeline of CC person will never be faster for getting of PR visa. Because after. issuace of File Number and UCI, what is counted as timer or time calculation purpose is the date of completenesss check and date of issuance of UCI number which will be same for both CC and DD person.
Hope this clears the confusion which most of the DD applicant has in their minds, that their applications are given less priority. I am 100% sure that it is not the case as far time of consideration/timeline of PR Visa is considered both CC and DD are equal. And DD is less risky and more secure. That is why everyone in the world advises to use DD.