Quick follow-up: what about blowing this discussion into launchpad under the rubric of "Manage CL syntax" or something like that.
I would prefer not to lose the discussion.
I believe this is a place where a tool like POIU or XCVB really veers away from vanilla CL usage.
Vanilla CL usage encourages* actions during building that side-effect the global state of the image. These actions may be bad if one wishes to build individual components in multiple different CL images. But they are natural to people developing code incrementally and interactively using a REPL.
I don't want ASDF to drift into being a tool that prescriptively moves people away from that practice. I think that's too presumptive for a piece of infrastructure. I don't think it's my job to wreck code, just because it's bad style. And I don't think proper use of the readtable or of pretty-print dispatch is obvious enough that people will recover well if we mess with it.
As you have said, I am inclined to be much more conservative about changes like this.
Best, r
* I am not endorsing or deprecating this encouragement.