How to clear a cached 301 redirect once you've gone there?
Can't be done, you say, short of deleting your browser user configuration and starting over?
Well, not quite. But close.
The Chrome developers apparently don't want you to ever succeed in this, because they don't provide an obvious way to do it, and from all the different solutions I tried, seem to be actively closing off various solutions discovered by users on their own. Why? Don't know. Don't care.
When Shift-F5, a long Shift-R and all of the tricks with Dev Tools or "chrome://" links don't work:
Find the Default Cache folder and delete everything that's in it, or just delete the whole folder.
On Windows:
C:\Users\[yourusername]\AppData\Local\Google\Chrome\User Data\Default\Cache
On Linux:
/home/[yourusername]/.config/google-chrome/Default/Application Cache/Cache