boylesg:
First of all bloody windows 10 won't let me have a file or folder named .development - it insists on a file name.
Yes, that's annoying but an advanced user can use the command line:
echo > .development
Once you've created one flag file you can copy it around all you like in Windows Explorer.
boylesg:
This this whole writable library thing sill simply not work for me without a simple option in File->preferences
Then you're not an advanced user and you should be saving copies of the modified example files to a different location.
boylesg:
It seems that I a far from the only person that is annoyed with this feature.
{{Citation needed}}. Note that in the issue I linked above the main desire was to be able to edit the library source in the Arduino IDE. The example sketches was a side issue but easier for the developers to fix. As for editing libraries, the Arduino Web Editor folks have said multiple times this is something on their roadmap so hopefully that feature will also make it into the standard IDE.
boylesg:
I vote for just getting rid of the f'ing thing!
I vote, against... Tie!