Is there a place that documents the rationale behind the design of commands?

[t-cadet]

I was tripped by the particulars of a few commands, for example what is mentioned in #3114 or in #1377.

I think it would be useful to document the rationale behind the design of each command.
This would make it easier to use the command effectively in an idiomatic Helix workflow, and serve as future reference to decide whether the behavior of the command should be changed.

Maybe this should be done by answering a set of questions such as:

• why is it useful to add this command to Helix?
• what alternatives were considered?
• why is this particular design better than the alternatives?
• how do I use this command idiomatically (examples)?

Is there already something like that, or is it planned?