[sillysaurus3]

Actually, it's not a small feature. It's a feature that seems small until you experience it firsthand, similar to the Apple II.

Beyond that, I don't understand any of the other objections. Low level code in a high level language is one definition of power.

[crazyhatfish]

Have you experienced it? If so, where can I?

I'm not saying its a bad idea, just that this direct path in implementation is.

There are many other (better) ways of implementing it, like the Mozilla light sensor API. If that doesn't satisfy you, you should create a new spec for light sensors combined with a practical implementation and then push W3C to use your spec over Mozilla's.