This guide is a curious Whitehall product after the criticism from the Chilcot Report; the publication - itself unusual - states:
‘The good operation’ is an operational policy handbook which crystallises the main lessons from the 2016 Iraq Inquiry report and other recent operational policy experiences to provide an induction tool, training resource and aide memoire for operational policy professionals in defence and across government. The handbook unites the Cabinet Office developed Chilcot Checklist and the Ministry of Defence Reasonable challenge guide, and has been developed with input from across the defence community and wider government.

It is 64 pgs long, quite a few blank pages and illustrations - after all it is a glossy handbook.

The introduction starts with:
‘The Good Operation’ handbook is designed to prompt its readers to ask the right questions as they plan for and execute a military operation, drawing in particular on the lessons of the 2016 Iraq Inquiry (Chilcot) Report, but also on other reports and on the experience of colleagues. While some elements of the handbook may appear self-evident, sometimes it’s important to restate the obvious. Though aimed primarily at MOD decision-makers, it is intended to have utility across the wider national security community.
How is the guide structured?
As a starting point, Partners Across Government developed a simple ‘Chilcot Checklist’ to provide a rule-of-thumb guide to aid decision-making during both planning and implementation; this appears on the next page and provides the structure for the rest of this handbook

So have lessons been learnt and implemented? Only time will tell.

I also think the handbook can be applied in other fields than national security.