Built in attenuators?

[Mr Wright]

I was looking at an ad for some of the huge orange amps and saw that some of the models have footswitch controlled (or footswitch defeatable at least) attenuation.

Has anyone built an attenuator into an amp?
What kind?
How do you handle the additional heat in the chassis?
What the heck kind of attenuator handles something like a 200w orange?

[d95err]

Afaik, it's just a ppimv (on those Orange amps).