I've used my all clad copper core with no issues, but don't know an official answer on that.

BTW, one trick I have used with the CC broiler to get around the rack position issue if to put the rack on the second position and then put a jelly roll pan upside down on the rack. This provides about an inch of elevation closer to the broiler for browning.

Yes, anything that can handle stove-top heat will be O.K. under the broiler. Avoid glass oven-ware it will not be O.K. because of the intense heat, likewise plastics (including handles on metal pans) and aluminum foil and silicone baking pans.

Technically you should avoid teflon coated pans as well since temps above 500 degrees start to cause it to break down.

-Stooxie

I have used my glass corningware for years under the infrared broiler, I also love using the cast iron skillet too.

Nice trick CT Rob, I too have found the second rack is too far away and the top is worthless...

Here's an official answer from All Clad (confirming the consensus here):

6. Is All-Clad oven-safe?
Yes. All five of the All-Clad collections are oven and broiler safe. Nonstick items are not broiler safe, but can be put in the oven up to 500 F.

Thanks Z!

CT-Rob, Emilner -- I pointed out this racks-positioning problem to the Capital engineer today. He said he'd look into the idea of adding additional slides to the stack. I think the racks need reengineering though.

He's also looking into some way to provide an internal thermometer for reading.

I mention this for interest sake -- I'm not suggesting you hold your breath waiting for the fix though! However, I would say that if you want to convey your well-thought-out ideas, I have no doubt they would be welcome. Please contact me offline if you need help finding the target for your great ideas and observations.