I was orderly, and I made sure I was killing something everytime I had a devil or demon up. DUring my cabal interview I kept a devil up and it turned on me. Tried to dismiss it early but dismissals (as usual) failed.
One thing I think I learned from this attempt is that your spell % in conjure devil seems to matter. Little tip is to conjure a tiny devil, dimiss it, and then spam the spell while you have a devil timer. I ended up getting consistantly better devils with about 90% conjure devil.
I have to say, that without the scion despoil ability, evil conjurers are pretty neutered. I had 600 hps, couldn't get an worthwhile edges @ 40 (had a shit ton of explore / commerce / obs / raiding / role exp), and even with A/B/S/stoneskin I wasn't seeing my devil casting anything meaningful on my opponents in the short span of time I could actually stay in a fight. If you flee, your devil's morale goes down. In pvp, all you're doing is fleeing. You don't have enough health to stay in a fight long enough for anything to happen. Leveling up is godawful. Leveling from 40-51 is probably even worse. Fuck it.