[@Divinity]
Hardly, as light is a specific area within the electromagnetic spectrum. Arguing that control of light translates into control of the electromagnetic spectrum is like saying that controlling metal lets you control all matter. Doesn't quite work that way.

[@Lmpkio]
It means that if he's attacked from behind or with the element of surprise, he's going to get a moment's notice beforehand. So he'll still be caught by surprise, but he'll be able to sense the attack moments before it hits him.