Worth getting narrower road bars?

[KnottedYet]

Stand straight and tall, and put your arms out in front of you with your thumbs up. Hold 'em out in what seems like a "normal" distance.

Ask your assistant to measure the distance from the web of one thumb to the web of the other while you hold still.

Treasure that measurement, that is your neutral. If you wanted a bar that was the same width as your neutral arm position, it would have the same center-to-center distance at the point where you like to place your hands as your web-to-web distance.

If you want something wider for leverage, add a some centimeters to your neutral width.

I've got bars that match my neutral on my go-fast bike. On my commuter/hauler/trailer-puller I've got moustache bars that are a good bit wider than my neutral on the tails. Looooove them, and had to do some searching for relatively narrow moustaches that were close to my neutral on the forward curves.

Knowing your neutral at least gives you a place to start.