With reference to Perry Beechs there is an interesting commentary on the Local Schools Network by Janet Downs here:
www.localschoolsnetwork.org.uk/2016/03/perry-beeches-expected-to-lose-academies-but-questions-about-oversight-transparency-and-responsibility-remain
The whole thing, and the links in it well worth having a look at, but the nub is contained in these quotes.
"The Guardian cited a ‘Whitehall source’ who said action taken by the Education Funding Agency (EFA) at Perry Beeches ‘shows the academy system is working, with the EFA identifying issues and regional schools commissioners intervening and rebrokering effectively, as part of a robust system of oversight.’ This is nonsense. It was not the EFA who identified issues at Perry Beeches but a whistleblower....
It’s not, of course, the first time the alleged ‘robust system of oversight’ has failed and where action was taken only after allegations were received by the EFA: Cuckoo Hall, Barnfield, Sawtry, Durand, Bilingual Primary School Brighton, Kings Science Academy.....
Far from being robust, the EFA oversight appears to rely too much on whistleblowers.
.....serious questions remain about how the EFA can effectively monitor the annual accounts of academy trusts."