"One thing I found very very helpful was my cast bar mod, and for the life of me I can't recall its name right now, but the last X seconds/milliseconds of the bar was a different colour, this different colour indicated a possible point at which you can cast another spell without interrupting the current spell. The length of the spell being cast would determine how big the 'lag' bar was. A flash heal caused a larger 'lag' bar but a greater heal caused a much small 'lag' bar. If I gave the voice command when the spell cast was in this 'lag' bar area it was almost an instant cast on to the next spell. As in there was no down time between casting."

Quartz.

And maybe move this over to Software?