A self res in trials isn't even scary. Inspect your opponents before the match, and if you see a sunsinger, just be prepared. Watch their kills and try to predict when their super is ready. Most people have their supers charged by the heavy round, so around that time whenever you kill the person running sunsinger, just stay on that orb with a sniper or be ready for the barrel stuff with a shotgun. If you and your team prep for the self res you can shut it down before the animation even ends. ^and because of how easy it is to stop, I would definitely not call it a crutch. More like a final fighting chance to fix a mistake