If I remember correctly, RD was sort of a Chrono Trigger spin off by accidect (the scenario writer hadn't planned it out as a sequel at first). Later, because RD was not widely played, they decided to redo RD proper, in the form of CC. This is according to an interview I believe I read in the Compendium.
Anyhow, in the same interview (with MK I believe?) I remember reading something about an outside force intervening and influencing Poore, but MK didn't want to go into it. Presuming that Crono and Marle were dead while the timeline in CC was split into Another and Home, then the real question is whether the outside influence still influences Poore after the events of CC (of course Lucca is alive, without the whole Schala interfering and bringing Serge into contact with the FF and Serge's father turing into Lynx thing). I wrote a couple of my theories down on some thread about Poore's militarism, I'd like to think that Belthasar was that outside force using Poore to help bring Serge to the point where he could save Schala, and then once Schala is rescued and the whole affair is unneccessary, he went back and undid Poore's militarism, allowing for a pretty happy ending. However, because of the somewhat vague ending, we can't really tell what happens (especially in relation to whether or not Chronopolis, FATE, and the Frozen Flame are still around spreading their influence in 1020 after CC, this would explain quite a bit I think, because though Project Kid is no longer needed, it was Chronopolis that created El Nido, and for Serge to live his life, El Nido needs to be around, however for him to live his life relatively unaffected FATE shouldn't meddle. (?)).
