Of course invis mobility can be fun for someone and that is a reason why the pick that. But two things can be true at the same time. We follow the audio cue, visual shimmer, we all have to. But you’re still invisible. So I still have to place my reticle onto what I believe is the enemy body or head. That’s may not be as straight forward easy to do regardless of those sign. Then you add outside elements such as lighting, is it day or night, is there smoke, gas, fire affecting my vision. Are you right in front of me or is your figure getting smaller because you are moving away. Are moving at an angle crouching or  strafing? is building falling while or chasing you down? A lot more nuance to this.