I wanted to move typefaces which had been installed to my ‘user’
collection over to the ‘system’ collection. There didn’t seem to be a
quick and simple top-google-juice rated article for this.
How did I do it? Well… drag and drop.
https://support.apple.com/kb/PH5955?locale=en_US details the locations
of the fonts directories, so a simple Finder/Go to Folder for
~/Library/Fonts/ and a new window for
/Library/Fonts and a
drag and drop later, bingo.
One catch: if you’ve previously run the ‘Look for enabled duplicates’
option, you may need to re-enable those fonts.
Nice and simple. And it works. Even on Yosemite.