The way a professional uses a headlamp isn't the way an athlete uses one.
You don't live at full output. You run the lamp at the level that lights what you're working on — and you keep it there all day.
At 50 lumens — enough for close work in front of a breaker panel, a valve, a wiring terminal — both batteries run for 36 hours. 18 on one. At 100 lumens — the level most people reach for when they're working steadily across a few meters — 18 hours on both, 9 on one.
That's a full shift on one battery. With the second in your pocket, the light is still there when the day runs long.
The 1,235 lumens is there for when you need to read a whole substation, a dark tunnel face, or a site at first light. See the space, understand the job, dim back down, work through it.