There is nothing wrong with memory overclocking, it is no more dangerous than overclocking your CPU. If the memory has no problems at faster settings as shown by memtest and a burn-in benchmark, then there is no problem. Besides, memory has warranties that cover overclocking damage so no problem there either.
You can even increase memory voltage to the maximum safe voltages and see if it will run at higher performance settings stably if you want. I've done it several times, there are no problems unless there would have been problems running at normal parameters.
RAM overclocking doesn't improve performance of most applications significantly, but it helps a little, especially in archiving and similar data intensive work.
So would you say that, based on what i've described, that I've not done anything incorrect?