Originally Posted by
Stommped
This is a lose/lose situation. In PVP scenarios where targets are Rooted/Feared/Hexed you would want Starfall to hit them because they are likely to be full dotted anyway, and the damage threshold to break the CC is likely to occur. Even it does break ~1 or 2 seconds earlier than it would have, it is not the end of the world because the trade off is some Starfall damage on that target.
In PvE you may want to keep a target permanently rooted while killing other things, aka Will of the Emperor. Here Starfall may hit your rooted target and break it early (it would probably be pretty easy to figure out how many Stars need to hit a rooted target before it can break), but there are still other factors. If they are multiple targets within your Starfall range, then only 2-3 stars may actually hit the rooted target, possibly not actually crossing the threshold and breaking the CC.
Normally in PvE situations CC which breaks instantly on damage is preferred. Sheep, Ice Trap, Bind Elemental see the most use in raiding today on Will and Lei Shi, and Starfall can now freely be used in those situations. There is no perfect sitauation for the other types of CC, other than making a glyph of Starfall to only attack your current target.