The workflow will work even if you don't have the same fonts. The problem you'll see is the same as if you opened an InDesign file and didn't have the fonts. You get an alert/warning, the text gets the dreaded pink highlighting (non-printing) which you can turn off in Prefs, and the line endings might not exactly match that of the actual font.

However it's all still fully editable. So the InCopy user could open the ID file in IC, check out the stories, edit them, check them back in, all without having any of the fonts used. When the ID user updates the editor's changes, they'll come through fine.

In the real world it's a lot more pleasant to see the fonts used. So usually publications take the opportunity to move to x-platform Open Type fonts to avoid headaches. PC TrueType fonts can be used on a Mac. PostScript fonts can be problematic because of diff. naming conventions. You could use FontLab's Font Converter http://www.fontlab.com/font-converter/ to convert any font to any platform or even to OpenType; some of my clients have done this for specialty fonts for which there is no OpenType version.

AM