An example from Daray:
"The following priority listing, shows the comparative dps efficiency of our spells at capped INT (1220), 40% base damage modifier, 100% damage spell crit chance (capped), and +1000 spell damage. This one closest represents my setup."
RoD is not a terrible spell. Granted I would not make it part of opening spell rotation as a wizard, but it is a great filler when it is up. I suggest not using it in an opening sequence because the other mages of their group have their own temp buffs running and their casting order to get started. Its just a curtesy...plus there are other things to get going on the mob before you hit RoD.
As a wizard, when you are in group with other mages, it is a good idea to find out how your group members feel about RoD.
I know a lot of Illys that love the spell. I know a lot of Coercers that hate it. I have had warlocks ask me not to cast it and I have also had them tell to cast it.
You do not have to put a warning in raid chat...it only affects group members. If it is a HUGE issue with some of your group members...you can create a macro to send them a tell warning them that you are gonna cast RoD in say 5 seconds as an example. Gives them plenty of warning if they want to get away from you. I dont send a tell to n e 1...I just have a generic macro attached to the spell when I am casting it letting my group members know I casted the spell.
Its all about knowing your group members and their preferences. Furthermore, it is a nice 20+k nuke to throw in the mix. If it is an issue, make sure you are 15m away from your group mates or they are 15m away from you.
We could always ask the Devs to make it a raid wide spell

JUST KIDDING!
So all in all...use common sense. If you are a retard...then I guess you are fucked.
<3