Hi Gareth,
Just an update..I was able to fixed this problem in FULL DTP by revising the codes in your doc:
Using ABAP with Process Chain Decision Processes
What I did is to compare the 2 latest requests in NEW_DSO..If they have the same number of requests, FULL DTP will not be done since I assume that no changes has been made hence NO CHANGE_FLAG will be present in the NEW_DSO..
I am already running the reports daily..Right now, almost all requests has no changes so I don't know yet if this will work..
But I already tested it using DUMMY providers and data and it's working fine 
(just not sure if I missed any scenario which could make the BADI incorrect)..
Thanks a lot for your time and help..
Loed