I haven't seen Doug Ritter's headlamp design. Based on my old traditions, I normally use Petzl headlamps (same ones that are often used by cavers and climbers).

The main thing about headlamps (don't know if this affects the Ritter design) is that they sometimes have the nasty habit of turning ON inside your backpack. It's easy for a bump on the pack to disturb the gear and switch on the lamp. And then when you take the light out and you really need it - the batteries are dead.

To prevent this, I either carry the batteries separate from the headlamp (usually attached on the outside with some Scotch tape), or I insert a small piece of cardboard over the battery terminals to prevent an electrical connection.

Headlamps are valuable for many reasons - but they are especially helpful during medical emergencies in the dark. They allow you to keep both hands free while you are working on the victim.

Pete