I think this conclusion rings true to anybody who has tried to seek out differentiation for their child. I have a feeling teachers - in moments when they could be frank - would likewise say that differentiation is a fraud.
As I've said in another thread, I volunteered to be on our school's "Site Council," a group that purports to put together the curriculum plan for the school. We are required to adopt a number of goals that can be assessed at the end of year by objective data.
The council is composed of the principal, the PTA president (who is a bubble-head) and an equal number of teachers and parents. As the planning evolved it became clear to me that there were several other parents on the council who joined for the very same reason I did. They wanted better support for their gifted children.
The goals being proposed by the principal and the PTA president were EXCLUSIVELY focused on bringing low-achieving students up to grade level. The other parents and I proposed multiple revisions that would loop in support for high achieving and gifted kids. The proposals were rejected in every single form. Even very small suggestions. For example, the math goal was stated as [something like] "reduce the number of below-grade achievers to some X percent of students." We suggested an add-on that said "and have at least X percent of all students make at least one year of progress in the math curriculum."
Now let me be clear - this is an elementary school in the very heart of Silicon Valley. High expectations are a default around here, and "high" is very high indeed. In fact, suicides at our uber competitive high school show that the high expectations are problematic in themselves. That's a whole other discussion. But my point is, this is hardly a community that would balk at goals focused on the top end of the bell curve. Especially since every parent around here thinks his/her kid is at that top end!

And in fact, having worked closely with the teachers and the principal, I believe they are very good educators, truly committed to teaching every student. They honestly try hard.
But this only serves to emphasize that differentiation in the classroom cannot work. If it could have, it would have here.
In case I haven't made the point clearly enough "differentiation" is a word tossed out as a bone to parents of gifted kids, as a shield so schools can claim they are helping our bright children, and as a tiny bandage on the damage done by denying access to gifted programs and tracking that would make them possible. Believe me, I'll keep plugging away on the Site Council. But I have no expectation of success.
And so in our family, the motto remains "Differentiation begins at home." Thus, this afternoon, we will be building the Lego Trevi fountain, researching how it worked in the days when there were no electric pumps, and figuring out why it is a sculpture of Oceanus rather than Poseidon (which made DS7 quite annoyed when he noticed it last night!).
Thank heavens for this community - where I learn over and over - it's not just me. I'm not crazy!
Sue