No, it won't be reliable. When you use a macro, the lines are not all executed simultaneously. There is a split second delay between each line executing. If you hit that a split second before your GCD finishes, you will see your second skill pop. With that macro, you will see a fair percentage of Stone 1 and 2s popping up if you blindly spam. I did the same thing with Broil and Ruin1, and I have had to train myself to time it instead of spamming it.