Hmmmmmmm. . . . . . . thanks Prasath, it appears that an object can have any one of a number of states, but one state only.
This doesnt really aid my situation as I had hoped.
I currently select a set of data in the future as it looks at a given point in time and compare it to a similar set of data in the past as at another given point of time within one object.
ie: Nov'12 as @ 1st Sep'12 vs. Nov'11 as @ 1st Sep'11.
ie: Dec'12 as @ 3rd Sep'12 vs. Oct'11 as @ 16th Jul'11.
I currently manage this within one object with the use of several date islands and set analysis. It's not pretty and I was really hoping that alternate states might make the process a lot easier.
I was also looking for some example material from the Developer I, II or III manuals which cover the subject in 'user coding' detail rather than 'sales talk' detail.