On differentiation: a reply to a rant and a posing of questions

If you are going to read one post this week, I suggest you make it Grant Wiggins's (reblogged here). The author of Understanding by Design responded to James DeLisle's commentary for Education Week, titled "Differentiation Doesn't Work". Like Grant, I also was surprised that DeLisle's piece even made it to publication. His commentary cherry picked quotes from other sources, poorly representing those texts on the challenges and benefits of differentiation.

What are your thoughts on differentiation, DeLisle's commentary, and Wiggins's response? Please share in the comments.