Davez, yes that's what surprised me when I applied this 21 day rule and found virtually no difference at all to S/R, so maybe I have just got a freak set of results here, or not enough results.
Problem is of course when applying filters is the enormous amount of possible combinations, i.e. if you have say 25 fields in the data base you could apply any of none, 1,2, 3, upto 25 can't be bothered doing the maths but its a lot.