I'm sure everyone remembers this LTQ:
http://www.funzio.com/forum/showthre...ht=walkthrough
This was one of the first faction LTQs where the XP gain was insane. Our faction beat the entire faction prestige and nobody gained any XP by doing exactly what you're referring to. We brought in newly created genymotion/bluestacks accounts, and could level them to 50 in about an hour using all stat points for energy, and using all energy to hit the necessary target. Never had to refill energy with gold, because the XP gains launched you through the levels and gave you refreshed energy each time.
This was not a hack, this was not a glitch, this was not cheating, and this was not against any TOS. GREE set the XP requirements for each target, and we were smart enough to figure out that if we brought in newly created accounts, we could let them do all the work for free. We laughed the whole way through this event while everyone else was on here complaining relentlessly. This was probably the only time an actual strategy that I can think of besides tap tap tap that was used to get a leg up on the competition. Don't hate because your faction didn't figure this out lol.
That being said, I don't think it's possible to do anymore. GREE lowered the XP for all targets after this event and I doubt we'll ever see something like that again.