From what I read u had 1 low geared Tank (may have had a ilv110 weapon cause rng sucks & was a 2nd job with no max 2.0 relic) only thing you could have done is wait 10-20sec after "EVERY" pull to allow tank time to generate arrgo then join in with Quelling strikes (I had to ask DPS one run back in 2.55 as my PLD was around ilv115 but DPS were a ilv130 with ilv135 weapon BLM/SMN... Keeper of the lake if I'm remebering right, granted once I got past 1st boss I knew how much I had to over-arrgo to hold it so I let them return to norm, it was a challenge to say the lest)

As much as I dislike funneling my own dmg for the sake of not pulling arrgo (or doing as I mentioned as an idea above) sometimes you just gota as its the only way to get threw an instance without it going all matter of arrgo crazy. Wether u lower u'r own power or say "F it" & keep going full tilt...or say "F this" & just leave... its really u'r choice how u handle situations like that.