So what's the fix? I want to GET something that has an 8k long name. What do I do?

I have an 8-foot toenail that needs a little clipping; what tool should I use?

More seriously, what needs an 8KB-long name?

(That bug post contains a few workarounds that'll let Drupal get back to GET for one of the listed cases. Drupal's case is particularly pathological as it's trying to be everything to everybody; it's like being a handsaw AND a sander AND a varnish for the floor AND a dessert topping.)

A file storage service, ala dropbox, that allows you to select multiple files and download them as a zip. The concatenation of several uuids adds up quickly.

Good point. Unbounded requests (hundreds or more of ten-char IDs) are definitely candidates for a POST workaround. It's a shame, but necessary. :S

My main beef with Drupal is that it uses POST for everything, whether it's to /jobs/1234 or to /files/?id[]=1234&id[]=3452&...

Use POST. GET is not meant for that amount of data. Alternatively, GET by a shorter ID.

What do I do about the people who tell me POST is only for actions which change server state?

You write a well documented application that is useful, adheres to as much of REST as you can and leave the theories to other people.

Simultaneously, it seems to indeed be a convention. And why not follow it? Do you have something whose keys really require the numerousness of 8KB of characters?