Async Google Docs > async Slack > meetings

You can setup a template with all they main points and checklists already in place, then get people to fill it out and collaborate on it.

Here's an example with the headlines, each would become it's own section:

    - Problem summary
    - Impact
    - Measure of success
    - “Why does this happen?”
    - Current solutions
    - Ideal scenario
    - Constraints and needs
    - Unknowns
    - Proposed change
    - Alternatives

And checklists for the writers:

    - On what level, and how detailed I want to describe things?
    - Did I write details into unrelated sections?
    - Who is this document for? Do they really know all that stuff I assume?
    - What impact would this change have on the business?
    - Can we quantify it?
    - How do we measure that the change solved the problem? How does winning look like? (ROI, proof of impact)
    - What is the root cause? (“Why? Why? Why? Why? Why?”) Are we solving the right problem?
    - Can we break up the solution into smaller chunks to reach the goal faster?
    - Are we trying to solve a general problem before something specific?
    - How do people solve this already?
    - Did we talk to them yet?
    etc.

Then you offloaded all the questions you would have asked anyway to a document.