Today it was the turn of the government's schools commissioners to face questions from MPs on the House of Commons Education Select Committee.
Dominic Herrington, the national schools commissioner, was accompanied by the regional school commissioners (RSCs) for the East of England and North East London, Lancashire and West Yorkshire, and the West Midlands.
The discussion ranged from their relationship with Ofsted during the pandemic to "tightened" academy regulation.
Here are the key points you need to know:
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1. Schools not expected to report to RSCs 'every five minutes'
Asked if a school that is not rated "inadequate" would have any interaction with its regional schools commissioner, Mr Herrington stressed that "one of the principles of the school system is school autonomy".
"So we wouldn't expect every school to be contacting a regional commissioner all the time, every five minutes," he said.
"A school may approach us if, as colleagues said, there's a decision-making function. They may approach us just for information or support, and they want signposting to something that the DfE [Department for Education] is doing. They may want some information about a programme that is being run, about an application, about a deadline, about a whole range of things.
"So there are things that schools will do, but we don't expect every school to be reporting into us, and I don't think that would be a good thing anyway.
"I think schools are places that should be teaching children, not reporting to RSCs every five minutes if they're doing really well and they're getting on with their work."
2. MAT system growing 'sensibly and prudently'
The national schools commissioner acknowledged there had been some "problems" in the academy sector in the past, but said the multi-academy trust (MAT) system was now growing "sensibly".
Committee member and Labour MP Ian Mearns pointed out that accountability may be "difficult" when RSCs have responsibility for a trust with schools spread across multiple regions.
"The contact there must be much more difficult in terms of that personal intervention," he suggested.
Mr Herrington responded: "Well, I think that's something that we've really tightened up on in the last two or three years.
"And you know, there was a time three years ago where there were problems in the academy sector, and that was one of the problems."
He added: "We've ensured that the MAT sector has grown sensibly and prudently over the last two or three years. And so I think there's been a much greater assessment – self-assessment, actually – within the MAT sector of risk, of growth, of sequentialising growth."
3. Regulation of academies 'tightened up'
Asked for a "practical" example of how MAT regulation had been "tightened up", Mr Herrington said: "So we've tightened up in the sense that we have a much tighter and more regular set of conversations with trusts. And that includes obviously trusts that are in more than one region.
"It means more regular reviews of their performance, it means more regular monitoring from the ESFA of their financial performance as well, it means much tighter relationships between ourselves and the ESFA, so that we have a sort of single approach to all of these trusts. So we've really tightened up on that."
4. Ofsted inspections of MATs still off-table for DfE
Mr Herrington was also asked by Mr Mearns if he agreed with chief inspector Amanda Spielman that Ofsted should have the power and duty to inspect MATs themselves.
He responded: "We've not taken that view as a department."
Pushed on this point by chair Robert Halfon, Mr Herrington said: "It's because the oversight of MATs is far, far tighter now. By RSCs and the ESFA working together, there is better understanding within the system.
"And there's less clamour for Ofsted, I think, to inspect MATs, because of the tightening up and the regulation."
5. Ofsted and DfE schools commissioners 'understand each other far better'
The schools inspectorate was initially part of the REACT (Regional Education and Children's Team) initiative when it was introduced to support the DfE's Covid response, Mr Herrington said.
However, as inspection has started again, the watchdog has "rightly" stepped back, he added.
The national schools commissioner said that, on reflection, the collaboration "allowed us and Ofsted to understand each other far better".
6. Backlog of failing maintained schools waiting for academy conversion cut by 62%
Mr Herrington revealed that the backlog of failing maintained schools waiting for academy conversion has been cut by nearly two-thirds over the past two years.
He said two years ago there were about 200 "inadequate" maintained schools going through the academy conversion process.
A year ago there were 149, and now there are 76, of which "most" will open this year as academies, he said.
7. Schools commissioners see their job as making NTP work
Asked about the government-funded National Tutoring Programme (NTP), Mr Herrington said: "Our job is to make sure that it works."
He added that the scheme is a "really, really important and vital part of the work to recover and to help the learning that's been lost".
"So I think that we would want to really support it, get behind it, and do what we can to help with it, to ensure that children can catch up from some of the days and education they've lost," he said.
8. But RSCs not assessing quality of online learning
However Sue Baldwin, regional schools commissioner for the East of England and North East London, said it was not their place to judge the quality of remote learning on offer.
She said: "In terms of the quality of online learning, that doesn't fall within our remit to assess that. That would be something that Ofsted did actually look at during their remote visits and their assurance visits."
9. NTP being promoted to academy trusts
Mr Herrington said the schools commissioners had been speaking to MATs that had the lowest take-up of the NTP to "correct any misapprehensions" around the scheme.
Asked what they were doing to ensure the catch-up programme was helping the pupils who had learned the least during lockdown, he said: "By talking to local authorities, explaining the programme, correcting misapprehensions, talking to multi-academy trusts that have high numbers of vulnerable children in them.
"And we've seen an increase in take-up recently, but I think our job has been to promote the programme, and to ensure that everyone understands fully what is on offer."
10. Schools commissioners not just another tier of bureaucracy but 'critical' to academy regulation
Presented with the suggestion that commissioners "are just another tier of bureaucracy", Mr Herrington said Ofsted plays a "really important role" in the system as an inspectorate, but "ourselves working with the ESFA are critical to academy regulation".
11. "We would have a problem" if they didn't exist
And asked by Mr Halfon if the world would "fall in" if schools commissioners did not exist, Mr Herrington said "we would have a problem".
He said: "I think if you look at what we do and what we've achieved in terms of reducing the number of failing schools, the oversight of educational performance in maths, the response to the pandemic in terms of helping schools and being the glue locally to often bring people together, yeah, I think we would have a problem."
12. RSCs want more resources
The regional schools commissioners were each asked if they felt they had sufficient support to do the job. Two of the three appearing before the committee indicated that more resources would be helpful.
Ms Baldwin said she did have "enough", but she would "always wish for more to be able to do more with".
And Andrew Warren, RSC for the West Midlands, also said: "Probably like Sue, we'd always like to have more to do more with."
13. Number of schools in NE engaging with NTP going in the 'right direction'
Last month, Tes revealed that more than four in five heads in the North East were not using the government's catch-up tutoring scheme.
But Mr Herrington said the numbers in the North East were now "going in the right direction".