The article says "By setting the maximum CPU frequency, while on battery, to 99% Turbo Boost will not be engaged." But one of the commenters after the end of the article says "I found that with my Surface Pro 4 i5/8GB I had to set the CPU max on battery to 90% to keep turbo off. Took hours of testing but that's the magic number for mine."
So my question is how do you know if you've successfully turned off Turbo Boost?