That's not quite the case, at least with the advent of Composure. Composure + Refresh = 7:30 duration, 450 MP return for 40 MP, giving the edge to Refresh. That said, /SCH is still hot for Chainspell Nuking as Crystan said (or any nuking, really), especially if you preload a Sublimation charge to add even more MP to your barrage of nukes.
Edit: Also, /SCH lacks Erase, which can be big in some cases.
I'm not going to give you too rough of a time about it (since from your sig's job list you're not a RDM, and can't be expected to know), but as a RDM if you are capable of covering a duty, you are expected to, no matter what it is. That means running a Haste cycle while Enfeebling and Curing (XP party), Crowd control while Healing and running a Haste cycle (Nyzul), Refresh BLM party while Crowd controlling (Dynamis), and any combination of those things.
"Haste > Paralyze > Haste > Slow > Haste" is all fine and dandy, but when you get into "Haste > Sleep Add > Haste > Dispel > Haste > Gravity" it will eat up all your Strategems, leaving you stuck in an Art that isn't the best for all your spells, or with no Art on at all, which makes you wonder why you didn't just /WHM or /BLM (as the case may be). Don't get me wrong, /SCH rocks in the right situations, but it's just that, situational, at least for RDM.
Edited, May 18th 2009 1:50pm by Aliekber