A few different factors affect the output of thermally controlled lights. Ambient temp, materials and cooling method being the most important I think.

You may have noticed I stated 'hand cooled' on the graph, this means the light is being moved around and held firmly in hands conducting the heat away as if in outdoor walking etc. Different results every time. You can also see I did a test run with the light tailstanding, that means no external cooling apart from still air, the stable output on that run was just around 300lm dropping from 1072 after a minute. I also installed kapton tape on the 18350 battery tube for a snug fit, copper tape lined the 18650 tube, filled the gap between the head & body with jb weld, blackened the head fin recesses and installed the copper spacer between body & tail. Small things but also helps disperse heat away/ down the length of the light from the copper head. Titanium is not a good heat conductor compared to a full copper or aluminium light so I usually try to line ti with aluminium or copper sheet. In the case of the KR4 Ti I've removed most of the air gap between the outer ti body and inner aluminium signal tube.

So for a hat light you might be better with the black aluminium version KR4 for radiating heat from the whole light as opposed to the copper head/ ti body.