No rifle should double because the second barrel's sear slips out of its notch or bent on recoil. If it does this then there isn't enough sear/hammer engagement and it needs repair.

Intercepting sears are merely a safety feature to prevent accidental discharge from rough handling, like dropping the rifle, and just in case the second barrel's sear does let go.

Doubling caused by inadvertently pulling the second trigger is not prevented by intercepting sears since pulling the trigger rotates the intercepting sear out of its position to catch the hammer.

I like them, and I like a bolted safety for the same reasons. In conjuction they render a traditional double safer than a Kreighoff since the Kreighoff cocking slide can, in theory, be moved forward unintentionally. Any suspicion of DG and the bolt can be moved, and it doesn't take much to move it - so long as you remember it - in the heat of an emergency either.

They are by no means essential to the safe use of a double rifle though, since you shouldn't be tossing any gun around and Rule 1 in gun handling requires you to know where your barrels are pointed anyway.

Hollowell's site has a photo of the sear and intercepting sear best seen on the bar action sidelock photo in its definitions section.

JPK