I have not heard any feed back about the idea of helping young students enter kindergarten and first grade at a more mature age, so they are developmentally prepared to do the important learning at those ages and mature to take advantage of college level programs in high school...and head off to college with more skills and confidence. Massachusetts (the Berkshires) has a two year program for the younger k'garten kids.
Many parents wanted that for all kids (and the work and options really do open up fast after first grade.