Please do look at the results of taking that matrix to different powers: https://www.wolframalpha.com/input?i=%5B%5B1%2C+1%5D%2C+%5B1...
What is this matrix doing? When you left multiply it, you're summing the elements of the left column and putting them in the top left (next fib number). Then you're moving the current number to bottom left (and top right). Incidentally, you move the previous to bottom right.
That's interesting!! It's very simple