Yes, we have done that, but the default is Grouped, so that is what users would be stuck with, which is unthinkable. It should be an Admin setting like some of the other options.
Two other problems found:
Preferences don't get saved correctly -- as soon as we move to another page, they revert to the defaults (though we found we could prevent that by removing all the Javascript from mylinks_preferences.html)
We can't use ASC and DESC as abbreviations for Ascending and Descending. We can change it in the preferences template, but we can't see what other changes have to be made for it to take effect.