The CESA/ODP thing is a self-fulfilling prophesy. A lot of talented kids play at CESA.
That said, I bore witness to a CESA player being held over this past summer when the player was about the 8th-best performer on the team. Even the player was surprised to be held over, based on evaluations.
When I asked, I was told a CESA-affiliated evaluator went to bat HARD for the player. No knock on the player. Good kid. A generally solid player. But a poor week.
As to tryouts, my proposal is simple. Hold 3: one each in the Lowcountry, Midlands and Upstate. Mandate that each player attend 2 tryouts, thus eliminating any questions about home field. Assemble a balanced staff of evaluators, who recuse themselves from evaluating their own kids.
It ain't rocket science.