The best thing the charter school idea did wasn’t to impose market discipline on KIPP or on the traditional public schools that KIPP is competing with for students. It was simply to allow KIPP to exist in the first place. That’s all, and that’s more than enough. Charters, it turns out, are just a way of allowing non-profit organizations to run really good public schools, in an environment that shields them from the horrible bureaucratic and political problems that plague traditional school systems. If that creates virtuous competition, bonus, but if not, it doesn’t undermine the case for charters.
This is a misrepresentation of history. KIPP was begun in the Houston School District by public employees of the Houston School District. Yes, there were struggles, particularly over space, but, as you may have noticed, space is almost always at a premium in urban schools, and is as much of a source of controversy today in the charter debate as it was when KIPP was a little extended-day program in a Houston Middle School. But if you read the history, what KIPP was doing was not dramatically out of sync with the rest of the district philosophically and supported by many important administrators through its early years.
Had KIPP simply become a local charter, it would be one of many successful local charters (like Times2 in RI, for example) that don't have much influence beyond its doors.
What "allowed KIPP to exist" in the form we know it today is charter law plus millions and millions of dollars in philanthropy and other support from an array of think tanks and other political allies (including key administrators in the New York public schools) that helped it spread across the country.
The other key factor is that accountability measures -- testing -- made it easier for them to make strong claims about the efficacy of their system.