Copying printer preset .plist files (Mavericks)

I am trying to copy a custom print preset from one computer to another. My understanding is that the presets are stored in ~/Library/Preferences with the name com.apple.print.custompresets.forprinter.<name>.plist. I have copied the preset into my preferences folder, yet the presets for that printer (a Canon ImageRunner 5075) have not changed.

In my preferences folder there is only the new file, and when I inspect it with the Property List Editor, the correct presets seem to be there, but when I choose Print, they don't appear in the Print dialog for that printer; instead the previous presets still show up. Are the preferences cached somewhere?

(The purely obvious answer "Just make a new preset" won't work for me, since Canon, in its infinite wisdom has removed print dialog access to the functionality encoded in the old preset, even though the printer is still able to use it.)

Any suggestions on how to get this working are greatly appreciated.