Yet his revelation of Prime Minister Boris Johnson s vulgar description, in a private WhatsApp message, of the capabilities of his own health secretary will garner the most headlines.
In truth, the most damning evidence from Cummings' files lies elsewhere.
The picture he paints - of panic, incompetence and dishonesty at key points in the Covid crisis - appears to be a primary-source insight into government through that period. It does not make for a pretty sight.
Cummings focusses on three mistakes: first, the belief that herd immunity was desirable and possible, early in 2020. Second: the failure to swiftly set up mass test-and-trace. Third, the "protective ring" around care homes which was anything but, leading to thousands of deaths.
He also alleges the wrongdoing continues today, with Hancock and Johnson rewriting the recent history books to pretend the early stages of the crisis were better managed than they were.
Enemies of Cummings will dismiss the blog post as as self-serving and barely-relevant indiscretion, garnished with post-hoc wisdom and laced with cold revenge. But its real value - and the real concern it provokes - is that it describes a period in government less than 18 months ago. Many of the people he accuses of dealing so inadequately with the crisis then continue to preside over an - at best - tentative emergence from the crisis now.
Moreover, "The public inquiry cannot fix this", writes Cummings. "It will not start for years and is designed to punt the tricky parts until after this PM has gone".
And on this, we agree with the Prime Minister's former adviser. Better that a more rapid inquiry, covering events across the United Kingdom, be convened now, to report back as soon as it can. Only by doing so can our institutions can learn where they went wrong, and can the electorate learn more of the circumstances in which grave decisions, with implications for the health, freedom and wealth of millions, were made. Trial by blog post is unlikely to lead us anywhere.