You should also not that VT and SW:P are the highest damage/cast time spells... since VT gets a 100% coefficent for 1.5 sec and shadow spec Pain gets a 140% coefficient also for 1.5 cast.
Also VE can be put up without pull any aggro, so starting with a VE, VT, SW:P can be done before the tank has enough aggro to hold a smite crit. So yes if you open wiht burst smite might win for a few secs... but dots will win in the end.
But now imagine 2 shadow priests in the same group since you assumed the smite priest had one... shadow weaving would be up immediatly and you could SW:D with almost no loss since you would get your health back within 2-3 sec and you'll never have to drink. Also in a 5-man my holy pally would just start meleeing and consecrating since I would hardly have to heal - since everyone would be getting >300 hps. Of course I do that anyways since I get bored.
For a normal 5-man you group composition doesn't matter as long as your tank/healer can handle it though... the point is that for dps a shadow priest is better utility and damage... and holy smite is closer to holy so you can be the primary healer a little better in instances. For soloing shadow destroys though with blackout, spirit tap, mind flaw, reduced fear cooldown...
Also VE can be put up without pull any aggro, so starting with a VE, VT, SW:P can be done before the tank has enough aggro to hold a smite crit. So yes if you open wiht burst smite might win for a few secs... but dots will win in the end.
But now imagine 2 shadow priests in the same group since you assumed the smite priest had one... shadow weaving would be up immediatly and you could SW:D with almost no loss since you would get your health back within 2-3 sec and you'll never have to drink. Also in a 5-man my holy pally would just start meleeing and consecrating since I would hardly have to heal - since everyone would be getting >300 hps. Of course I do that anyways since I get bored.
For a normal 5-man you group composition doesn't matter as long as your tank/healer can handle it though... the point is that for dps a shadow priest is better utility and damage... and holy smite is closer to holy so you can be the primary healer a little better in instances. For soloing shadow destroys though with blackout, spirit tap, mind flaw, reduced fear cooldown...