What will this revelation mean for Rhee's campaign to promote her test-driven reforms? Her theory seemed to be that if she pushed incentives and sanctions hard enough, the scores would rise. Her theory was right, the scores did rise, but they didn't represent genuine learning. She incentivized desperate behavior by principals and teachers trying to save their jobs and meet their targets and comply with their boss' demands.
Rhee's advocates point out that D.C. scores went up on the National Assessment of Educational Progress, the federal test. This is true, but the gains under Rhee were no greater than the gains registered under her predecessor Clifford Janey, who did not use Rhee's high-powered tactics, such as firing massive numbers of teachers.
I think that this type of issue is another reason that making testing into such a high stakes gamble may be problematic -- it could massively incent poor behavior (at all levels). Furthermore, that a more humane approach had the same absolute level of improvement as the draconian approach is worth noting. I am sympathetic to arguments that education is important but it seems that dramatic reforms aren't really beating incremental reforms. I suspect that this behavior may be true of many complex systems (and learning is nothing if not complex) that are challenging optimization problems.