Thanks for figuring this out. While reading the diff I realised that I have no idea what this PEP517 is about, and why I might want to (not) use it. Is there a short explanation of what the PEP does? (I've read the abstract of the PEP but left none the wiser) Similarly, why do we need this new flag to pip? Is it because newer versions of pip behave differently from older ones? Asked differently: why do I not seem to need this flag?

Do we need to add the -v flag to the commands where it wasn't already present? I don't know what the rationale is for some of the commands having it and some not, but for me pip already prints "two or three walls of text", which results in me mostly not reading what it tells me (I know ...). Which makes me wonder if turning on verbose mode helps people who are trying to debug something or if it adds yet another wall of text?

The pedant in me would prefer if we spelled out all the command line flags (so -e -> --editable). But some of the commands are becoming pretty long (see above for "wall of text"). What is your thinking?

And finally, some times we explain what --no-build-isolation does, but we don't explain any of the other flags. Back when it was basically the only flag it made sense, but now maybe we should just not explain any of them? Or all of them?

I have no idea what pep517 does, and I don't really care (it's given me headaches). But w/o it, the --no-build-isolation basically has no effect in build time and the command builds the whole package from scratch, which is not what we want. We want it to build only changed modules. I personally use make in instead, some people use python setup.py develop instead, but I guess we want to recommend the pip command here.

The -v makes it show what's being compiled, w/o it, it's just a very slow command that you don't know what it's doing. So I'm a strong +1 for both these changes.

I don't mind -e or --editable, I guess the diff here is just to make the consistent. We can also merge this PR and then figure out if we want to explain what pep517 does in a separate PR. But that doesn't really have an effect on our contributors. Right now, our docs don't give the right tools to first time contributors.