First of all this is not an argument. This is a friendly discussion about the ways to figure a brace length.
Hopefully the original poster, Floyd, will learn something from our two methods of doing the same thing.
I had a student here once, who told us a story about getting an "F" on an exam at college. He said the test was to get the answer and show you work to prove your answer was correct. I don't remember if it was a math test or what. But anyhow he got the right answer but when he showed his work, (how he got that answer) it was not the way the professor had taught them to do it. So that's why the professor gave him the "F" on his exam.
He protested this "F" and stated: "but I got the right answer"....
Finally the professor gave in and gave him a good grade.
It doesn't matter how you get the right answer. There are many ways to get the right answer. And discussing these ways teaches us all how to do it, more than one way.
Which way is better? That could be a personal opinion.
On my framing square are the dimensions for the brace layout including the diagonal dimension. I don't have to do any math at all. I just need to read the numbers and layout my timbers so that they all line up. Go together, be strong, and look nice.
Jim Rogers