Chris Woodhead, the OFSTED chief, believes he is able to operate more independently because he has no policy-making role.
But Mr Clark says: "OFSTED makes recommendations in its reports and then simply walks away. It doesn't have to live with the consequences. I believe it is very important that HMI should continue to be involved in policy so policy is informed by the extensive research evidence gathered through inspection.
"It is also important that HMI engages with the results of its inspections. The Inspectorate must be involved with schools and authorities in providing evaluation, advice and support."
Mr Clark says it is in any case "naive" to suppose that OFSTED has no voice or influence over Government education policy.
He believes criticism of the Scottish approach is a "distraction" and adds:
"It is interesting that some directors of education seem to have the time to comment on these matters rather than concentrating on delivering a high quality education service."
Mr Clark, head of Galashiels Academy for four years before joining the Scottish Office in 1989, also dismisses charges that HMI has been responsible for forcing through "top-down" changes such as Higher Still, 5-14 and target-setting which have then had to be "rescued" by education authorities.
"The Scottish Office actually has a good record of involving the profession, as I well remember having sat as a member of innumerable consultative groups and working parties. The idea that HMI goes into a darkened room and dreams these things up without any input from the rest of the profession is just nonsense."