Well, here(tucson) as a matter of fact and its not hot enough long enough to support monitors. Where monitors occur, its common for temps to be above 130F most if not all of the year.
The average ground temp in the sun in good old Tucson in the summer commonly exceeds 130F and at times exceeds 165F. And yes, lizards are commonly using those areas. This is not even considering the temps of the best heat sinks, as they are far too hot.
I do field work with montane rattlesnakes and our site is at 6000ft. There are temps there in the winter, in fact today, that exceed 140F. Of course thats too hot for the snakes. They choose areas that have ground temps that reach 100F or so. And yes, they are active today too.
I have taken my heat gun to Australia and I found the surface temps there to be much higher then surface temps here, with a comparable air temp. (I really wondered what the custom inspectors thought of that heat gun)
In fact, in winter there were areas so hot, that the monitors had to seek areas in the shade to live(top end)
Althought I have not recorded a temp in nature around 200F.
In captivity, its a totally different approach. I used temps where the hot spot reached 200F, not for the monitors to use that exact spot, but so there were be a larger gradient for the monitors to choose from. For instance, if the top of a retes stack is 200F the next layer(dark) is 135F, and this is the choice I was after. But much to my surprise, the monitors would indeed use the 200F hot spot at times.
About folks burning their houses down, well my field partner is a captain at the firehouse and other firemen commonly go to our study site and help. I also get to ride along with them. After hearing their stories, people do not need heat lamps and lizard hotspots to start fires or injure themselves. They can think of all sorts of inventive ways to do so. My partner(by the time they make captain, they are a bit jaded) calls these types of people, job security.
There are many concerns here, first of which is experience. There is a difference between newbies and experts. Even if this forum refuses to recognize it. What that means is, not just experience with monitors, but more importantly experience with the tools used to support monitors. Learning to use the tools is as important as understanding monitors. Heat lamps and electricity are tools. Failure to apply those properly can be dangerous to monitors and people. Same with power tools from Home depot and Lowes. I wonder if power tool injuries have risen since the masses can now buy cheap power tools from discount stores???????
So yes, with anything you do, you must first use common sense. But unfortunately, common sense if not applied equally amoung humans. And obviously is not often taught in schools. FR