It's a clever idea, but of course a MUCH more convenient way is to set up a free group calendar at CalendarHub. (Full Disclosure: I'm affiliated with CalendarHub.)
By passing around emails with an ASCII, monotype text representation of the possible dates and times, each person uses a symbol to indicate their preference and availability.
Tuesday, November 29, 2005
43 Folders on Group Scheduling
43 Folders reports on a funny lo-fi way to find the best date for an event based on several people’s schedules: