No, the code is open source so you are correct. The thing is DA is in the process of eliminating the possibility of being able to add an alternate credit schema to the code by making other various essential elements of the code dependent on the CreditNew code.
Bottom line: In the near future if a project does not want to use CreditNew then they will have to do some serious rewrite of a good portion of the server code. Since many projects do not have the time/patience/skill to do that, CreditNew will be the de-facto standard.