Round robin/cast sequence type thangs

I'm currently using a ghetto /castsequence macro for a basic round robin of fear bombs and death coils. It looks something like this (one line for each toon):

/castsequence Psychic Scream,,,
/castsequence ,Psychic Scream,,
/castsequence ,,Howl of Terror,
/castsequence ,,,Howl of Terror

Unfortunately it rarely gets me more than 1 or 2 fears. As with most pvp encounters there are a lot of cc's, a lot of LOS and target facing issues, so there's always button spamming. Despite my best efforts I always end up blowing 2 or more of the fears on the first try, and other times I just get stuck half way through the macro with the next in line being dead, or oom, or for whatever reason just not casting fear.

I looked at wowwiki and didn't see a delay condition (was thinking it would be nice if you could do /castsequence delay=1.5 psychic scream,,,) to prevent me from doing this.

Same issue with death coil - I almost always end up blowing both at once (although not always a bad thing).

Any help would be appreciated.