Why Clinton's Not Releasing Her Delegates

So what's the difference between Hillary Clinton's urging her delegates to support Barack Obama on one hand and formally releasing them on the other?

On last night's conference call, Clinton advisor Harold Ickes explained to the delegates that historical precedence did not call upon Clinton to do so. There are other reasons related to DNC rules. In theory, states could reslate their delegations and deprive Clinton delegates of their convention experience. And more parochially, an audience full of Clinton delegates ensures that when -- not if, but when -- Clinton speaks at the convention, she'll be cheered. Another argument, I suppose, would be that the delegation ought to reflect the primary results for the sake of the historical record.