Line-out with speaker simulation

While eshtablishing the specs of my yet-to-build A15MK2 with footswich, master and line-out I stumbled upon this site
http://www.richardbrice.net/hot_lamp.htm

It may be a useful addition, someone tried anything like this on his madamp?

When I've finished the amp i will try it and post the results but this may take a while, I'm now building the chamber in which I can build the a15 (I've got a 2 and a 3 year old, high voltages must be impossible to reach for them)