I am not a DNC and i do not know how RV works as regards is it instant TP getting, or builds up like Meditate. I did 2 stage SCs on DRG/SAM using jumps and meditate after a WS to self SC (yes it did work, tis all about jump gear swaps XD) before Samurai was stripped of the title of Skillchain God and every tom *** and harry could get access to sekka. Using all what the SAM SJ offers a job should allow a 3 stage, espech to a TP happy job like DNC.
Kinda like, put RV (and if ur subbing SAM, meditate) after ur 1st ws. That way say for arguements sake, from 200%tp (or less if ur STP matches a reasonably geared/merited SAM), this happens:
Sekka
Ws1
Med and/or RV
Ws2
wait a few secs, use RV here if dint before (as i say, no idea how RV works)
tp hits 100% again, final WS.
Remember u will get the odd shot in between Ja's, again adding TP to ya bar.
From a SAMs point of view that would give you a emulated 2hr with the right ws's, and i usually put this into my 2hr regieme to kinda double the amount of SCs (stole the idea from something on Wiki, =D).
If this order of events work, prob go for what Wilsner said as regards Darkness. You can always use some form of SC calc once u get the progression of Ja's right, and just macro it for diff SCs. :)
EDIT: long post and slow typing = missed Dreamers explanation of RV =p