It just doesn't work that way Martin. If they are not at the specialist school from the word go they loose critical time in that speciality, as you well know. Furthermore it is far harder to change schools half way through, as the different schools will use different examining boards with different syllabi - the exception to this clearly being at the start of 2-year exam courses.
Frankly though, we are not going to agree about the best way forward so I do not propose to continue with this argument!