A couple thoughts:

* You can use Earth Shock all at once for a single interrupt and/or instant DPS. Nothing shocking here. (ok, bad pun)

* You can put Earth Shock on round-robin in keyclone or use a /castsequence macro so that you can spam interrupts on someone by repeatedly mashing a single button.

* You can mix shocks as you suggest.


My personal strategy is 3 buttons:
1.) 4xEarth Shock simultaneously
2.) 2xEarth Shock, 1x Flame Shock, 1x Frost Shock simultaneously (Get an interrupt, a snare, and a DoT all at once)
3.) Earth Shock Round Robin


I might consider subbing in a frost shock to 1.) above, simply for the utility of it.

"More better" for PvP depends on who you're fighting and where (and how many opponents, etc). 4x Earth Shock is a good combo with LB+CL for a finishing move, but only against 1 person. I don't like having my shocks all on cooldown if there's other active players nearby that I might want to interrupt. 2.) has same problem, but at least there's some utility or versatility-- doesn't matter who the opponent is, the all-shock treatment has something for everyone.

#3 is probably most useful for PvP (particularly if you combine it with Vyndree's grounding totem spam /castsequence). You can emulate #1 by mashing the key over and over quickly as well.