Fatigue vs Large Parties: Exploit?

So, I had come to the conclusion that fatigue did not work. I could not have been more wrong. My sp party had been consistently running with 8-11 people, but one took a day off and stopped getting bonus from 2 people another wanted to take a day off and craft, and a third just doesn't want to faceplow into fatigue. So anyway tonight we only had 5 people, and let me tell you, IT SUCKED. First of all, same mobs we had been killing were giving a 1 dmg to .5 SP ratio instead of the normal .75-.8. Furthermore, we were all seeing extremely less frequent procs. Now that that is out of the way:

Is leveling in a large group with fatigue an exploit or intended to force people to not solo?

First point, the more people in the group the higher the dmg:sp ratio, which completely counters the ratio reduction from being in bonus. On Monday night this week, before bonus reset 4 ranks and 3 levels deep into bonus sword skill, tracking my sp/hr over 3 hours yielded 11.5, 13, and 10K sp/hr in a I believe we had a 9 person group that night. On Wednesday after it reset, my first 3 hours were 8K, 11.5K, and 9K sp/hr without bonus, in a 7 man party. Something is wrong with that. We know bonus works, we can clearly see it in gathering and crafting SP as well as physical level XP, so the variable must be party size.

Second point, I have been tracking my sp/hr for 3-5 hours a night every night since 25. All the way from 25-43 I have consistently been between 8-12K sp/hr, regardless of mob level. The only variable again here is party size, and adding more people will consistently increase your SP/hr until the point you are out killing the respawn of the camp.

Third point, the mobs with the best dmg:sp ratio have almost no HP and die after everyone in a 7-9 man party has gotten 2 hits, 3 tops. BUT, even on those mobs I almost always get a proc. Fighting those same mobs tonight in a 5 man party, I was seeing the same amount of procs getting 10 hits on a mob as I was when I was hitting it 3 times before it died with a bigger party and the 5K sp/hr proved this is not just me going "wow this sucks compared to last night" without proof to back it up. On the flip side, the mobs that give bad dmg:sp ratio and take a minute plus to kill even in 7-9 man groups give amazing debuff SP. Using weapon skills that put up debuffs or taunting and provoking yield excellent returns on those mobs, making them worth killing.

This should be noted that, at all times, everyone in the party is actively fighting every mob. Sure there are times where 1-2 people go afk to get a drink or use the bathroom but even if we wanted to, there are simply just not enough people our level to intentionally have people go AFK just to boost our bonus.

So do you think this is a gift from SE to allow the hard core players to reach level cap faster, or is it just something they overlooked and could possibly be considered an exploit?

I cross-posted this on both the zam and core forums for further discussion.