Momento (&c.)-esque scenarios/campaigns?, Anyone tried? Options

[Ka_ge2020]

As the name/description says, I was just wondering whether anyone had tried the kind of a-sequential, perhaps reverse-sequence scenarios as part of a campaign, with their groups? If so, any advice? If not, erm, any advice?

I've just been kicking around the idea of a multiple-period referential campaign that plays around with 'dream sequences', which are less dream sequences and more... well, what is actually happening in one of the periods in question. This is also partially a manipulation of the players themselves that, while normally a 'no no' of GMing can lead to some rather interesting scenarios. (This from experience based upon the assumption of the reality of given situations based upon previous experience and what they 'can expect', i.e. compare with assumed reality films like Fight Club, eXistenz, Thirteenth Floor, etc.)

One potential problem is in the 'yellow plot road' (as in 'follow the...') approach to PC destination, i.e. the idea that the final statistics, etc., of the character is determined before the game is concluded. In that that there is a question. For a 7/8 adventure campaign, what is a 'reasonable' amount of karma/experience to be awarded. I know this is obviously dependent upon the situation, but I might need to have to extrapolate characters based upon the pre-established preferences of advancement by the players. (This is similar to the advancement protocol found in Amber DRPG, so not too unusual.)

If I've posted this to the wrong forum, then my apologies. Just thought that I would root out advice and ideas where I could...

Ka_ge