I never really did slidecast above 0.5s due to unreliable results, so that wasn't really an issue for me.

Quote Originally Posted by Waliel View Post
/ac "Buff 1" <me> <wait.1>
/ac "Buff 2" <me>

You only need to press that once, but it adds one second (lowest possible, whole numbers only) of wait time between casts.
You can use <wait.0.5>. It works with decimal numbers, but 0.5 is pretty bad since the tiniest amount of server lag will break it.