I don't get it, and if this is true then I need a very careful explanation of the units of measurement and physics such that a 1 degree K (or C) equals ONE PERCENT.

Ah, right, I think I see what you don't get.

It doesn't make any difference how large a unit Kelvin is. Let's imagine I create a new absolute temperature scale. We can call it Seulcius! And 1S == 2°C (== 2K).

Now, the difference between freezing and boiling water is 50S. But I can still say, "101S is 1% more energy than 100S". Which, in Kelvin, is like saying, "202K is 1% more energy than 200K".

There is in fact an absolute scale that uses Farenheit spaced units, called the Rankine scale. And 101R is 1% more energy than 100R.

If that hasn't made it clear, think of it as distance. If you have a standard length Stride, then 101 Strides is 1% more than 100 Strides, whether the Stride is 10cm or 20 miles.