Displaying duration1, duration2 etc in the Gannt chart

[Michael Longdin]

I'm using Project (Pro) 2003.
Is there a way to create a Gantt view that uses the duration1, duration 2
(etc) fields for displaying the length of tasks rather than the standard
'duration' field?

I want to show some comparisons of project schedules based on different
durations of tasks in the same view?

I read somewhere about Optimistic, Expected & pessismistic duration but
these fields and the Gantts that are associated with them seem to be
avaialble to me.

Thanks

Michael