I didn't hold it close, either. There's a metal mesh at the open end of the SearZall cone. It gets red hot and emits infrared heat. But a bit of flame makes it past the mesh. I kept the flame off of the steak I was trying to sear.
It went slow. I thought that the steak may have been too wet from the juices that are captured in the SV process so I stopped three times to dry it. No joy.
I had more than one steak to sear and could see that the first ones would cool while I was was searing the others. so I finally used frying pans on my gasser.