To give the community some credit...I had two of three wait for me to figure out Diabolos through two test runs. We added a new party member, and finished it like we'd all done fifty runs of Ampador. The one dps that left just said 'I'm out' before leaving, no insults or otherwise. I honestly felt bad, but as soon as I figured it out, we had an easy run with the new dps that joined us in progress. Not every duty finder party comes with impatient people.