The best rule of thumb IMO is to only inform the group about things that they *need* to know.
We assume that the slower is slowing, the debuffer is debuffing, the healer is healing, the dps folks are assisting, etc...
However, there are some actions where the rest of the group needs to know *when* you are doing them. Specifically, when you are doing something that is a "trigger" for someone else doing something, you should probably send a message to the rest of the group.
So, when you successfully slow a mob, that's a good thing to tell the group. Healers change their rate of healing based on whether a mob is slowed/unslowed. Tanks will additionally adjust their agro generation based on that as well (it's kind of a sprint for agro at the beginning to counter slow/debuff agro, then a different pace for the rest of the fight). There can be a significant improvement in group efficiency just by having everyone get that message.
Slow failures aren't really that critical. Assuming you *always* send a message when you succeed, then I don't really need to know when you fail. I can simply assume that the mob is unslowed until I see the slow message. I can even realize that if I don't see it for a bit, that you might be getting resists. Both the tank and healer (assuming it's not you) can and should adjust to that as needed. I personally don't see a need for a "slow resisted" message, but if you have an extra hotkey button available, it probably can't hurt to have one and use it if you get a couple resists in a row.
I don't need to know if you've snared the mob. I assume you've done so. This one kinda goes the other way. I'm not going to change my process during combat based on when you snare the mob, however, if you *never* snare it for some reason, then I do need to be prepared to stop a running mob. So snare resist/immune messages are useful to the group.
Quick heal messages aren't needed. If your heal spell casts in less then 5ish seconds, by the time I see the message and realize what it's saying, your heal has landed. It really doesn't matter. While there are some situations with multiple patch healers where those kind of messages might be needed, that's pretty situation specific. Generally, I don't need to know when you're casting a normal heal.
CH messages *are* useful, however. Since CH takes a long time to cast, it's pretty nice for the group to know that it's comming, as opposed to the cleric just falling asleep or something (don't laugh! I've had that happen. It sucks...). As a paladin tank, CH messages are super useful to me since I can judge the rate at which I'm taking damage, and choose to drop a stun or two to give that CH time to land if needed. While it's not a huge deal, it kinda sucks to waste time stunning a mob for the last 4 seconds of a CH cast when I wouldn't have come close to dying anyway. If I'd known about when it would land, I could increase group efficiency dramatically by waiting for it to land, and then chaining a couple stuns so that the cleric has 8 more seconds before he has to worry about dropping the next one.
"Assist Me" messages are needed. This is not absolute, but as a tank, I always keep one ready. If there is any confusion at all about the target or when to attack, I can clear it up with a single push of a button. Again. The group will change their actions based on the message, so it's a useful message.
"Assisting %t" messages are *not* needed. I assume you're assisting me. I don't need a message in groupchat everytime you do it. In the same vein, I don't need a message everytime you nuke, or dot, or whatever it is that your class does normally every single fight. I assume you're doing your job. I only need to know things that will affect how I do my job.
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King Nobby wrote:
More words please