RAFT Writing strategy

Taking the Massachusetts Sheltered English Immersion class, I came across a writing strategy that seems to fit the mold of authentic assessments.  This writing strategy is called RAFT (Role, Audience, Format, Topic).  Basically, you provide a list of different scenarios in which a student can write about in order to approach a particular topic.  This gives the student a bit more ownership in choosing the role that they are most interested in.  

If anyone reading has some experience using RAFT, or something similar, please comment on what has worked for you in the past.  Here is a sample that I created on the roles / job requirements of leaders in each of the three branches of federal government:

Role	Audience	Format/Genre	Topic	Assigned to ELL? Which level(s)? Were your students able to access the content with this role?	Language Functions
Newspaper Advertisement Writer	American public	Advertisement	Need new applicants to run for the Senate and the House of Representatives.  What is needed?	1.       Yes 2.      WIDA 3, 5 3.      With assistance and sentence frames	Reading, writing sentence frames, Drafting an advertisement
Outgoing President of the United States	New President of the United States	Letter / Explanatory	Describe the many roles of the President of the United States	1.       No 2.      N/A 3.      N/A	Reading, writing a letter.
Justice of the Supreme Court	The diary of the Justice	Letter / Explanatory	Typical day as a Supreme Court Justice	1.       Yes 2.      WIDA 5 3.      Assistance with given summary of reading	Reading, summarizing, writing a letter

ELL = English Language Learner

WIDA = World-class Instructional Design and Assessment (tools for teaching ELLs)