Are you saying that versus a single target Shock is better than Force Lightning? That doesn't sound right.
Besides, I thought Crushing Darkness (with wrath proc'd) was better than Chain Lightning or Shock for single target damage?
i mean you would have better dps output while casting FL and CS on cool down rather than FL alone
You always cast your FL when you can. And juggle between death field, crushing darkness, chain lightning, chain shock, afflic. Be watchful with your cool downs. You FL all the way but when these cool downs are up you have to unload them.