The program clock blocker stops the clocks from dropping in the drivers when crossfire is disabled.
It works with 15.11.1 too.
The fluctuating clocks was and is present before the Crimson drivers. So the devs need to also look at earlier drivers to see why it is doing it and not just in Crimson. Windows 10 drivers are rendering great graphics cards useless. No graphics card should be dropping the clocks when gaming especially with v-sync off and also when having crossfire disabled.