"Who's in charge around here?"
For many guilds the Guild Leader is the Raid Leader and the recruiter and the one shouting "Come on guys, you've got to get better". The problem is that this way of doing things fails to understand and then proficiently execute the various things that need doing. Expectations can become unclear, goals are nebulous, and everyone is suddenly expected to be on the same page and just as competent as the loudest disgruntled in voice chat. This voice is inevitably not the raid leaders.
Approaching your raid team with the mind set that this is an organization with goals to be met and understanding the various positions that need to filled can be a great way to minimize stress and increase not only performance but also the enjoyment of the guild as a whole.
Let's break it down.
The heart of any Guild is the leadership. The Guild leader in particular is the person who gathers all the pieces and binds them together. This doesn't not mean however that the GL must be the lead of every little thing or know every little thing. A good GL, like a good boss, knows how to delegate work to the appropriate people.
That said it is the GL's responsibility to insure that the guild has a clearly defined set of goals, expectations, and plans to achieve such.
A guild without members is just one asshole spinning alone.
Recruitment is the life force of any guild. Whether you just invite your 24 best friends or you go out and persuade a thousand people to hangout with you on Friday night you have to understand how to get people into the guild and how to keep them there. If you aren't the best recruiter then your first goal should be to find a recruiter. Once on board, or if you are doing it yourself, decide what your goals are and insure that you are recruiting for that purpose. Remember to be realistic about this as well as it is difficult to recruit people who are above your level of play. Make sure to clearly define what is expected of recruits. A social guild might decide to set an activity minimum while a raiding guild would want to be clear about how progression will take place and be tracked.
This doesn't require long contracts with multiple witness signatures and lengthy interviews either, simply insure that the recruiters explain what it takes to join and remain within the guild. Also be on the lookout for raiders who have higher expectations than you are realistically ready to meet, too often this leads to frustration and a foul atmosphere.
Once people join the guild the GL just has to insure that they have an ear to the ground and are ready to handle any drama that may come up. Additionally the GL will set the bank up, give privileges, assign officers, and insure that all the various groups within the guild are functioning as intended.
If the guild plans to cater to a social atmosphere then it will need to have someone in charge of deciding what that social atmosphere will look like. While this certainly could be the GL it doesn't have to be.
At the very least the social officer should be aware of who is who within the guild. They should know what alts are in guild and who in the guild are related IRL. Additionally a good SO will be up to date on guild gossip and drama and will be able to inform the GL of potential problems before they explode.
Going above the party host an SO could be in charge of setting up casual events for guild members. Things like transmog contests, raffles, old raids, or alt runs. The SO should also be able to direct new players, or those who simply need more information, towards resources that can better help them understand the game.
First things first; the raid officer is not the raid leader nor does the raid leader have to be a raid officer. Even if the same person occupies both roles it is crucial to understand that these are very different jobs. The biggest difference is the raid leader is only active during raid time while the raid officer is always on duty, so to speak.
The raid officer is charged with executing the GL's raid vision. Again, these could be the same person but they do not have to be and in larger guilds probably should not be.
The RO is charged with setting realistic goals for the current Tier and insuring that raid recruiters are recruiting people who understand these expectations. If there is going to be a performance floor, and there really should be for anything other than a beginners team, the RL needs to insure that these standards are clearly stated and that all raiders understand what is expected of them. The RL should have the tools needed to monitor performance and the intestinal fortitude to enforce those standards.
Once the recruiters have populated the raid team(s) the RO must maintain the roster and decide who will be on which team and who will be sat. They should let raid leaders know who has priority seating on the team and if anyone is completely banned from raiding. The RO should work with the GL to make raid consumables available and insure that repair costs are met to the extent that the guild has decided it will provide these things.
Finally the RO is charged with setting the raid schedule and insuring that proper notification goes out to any changes that may come up.
Back in the forty man days guilds often had class captains along with role captains but today the RL can get away with a healing captain and a DPS captain leaving tanks to self regulate so long as serious issues with tanks do not crop up. The RO should choose from among the raiders who will be in captain spots. It is best to choose players who show a knowledge of finding solutions to problems with ease.
Role Captains are charged with monitoring the members of their particular team who are in a given role. Because of the limited number of tanks in any given raid it is unusual to have a tank captain.
DPS Captains should be knowledgeable of average DPS numbers for a given fight at a given ilvl and given spec. This information is not difficult to find for someone who has experience using logs off of sites like warcraftlogs. The DC should monitor the performance of their teams damage dealers to insure that everyone is pulling their weight. They should also be ready to provide helpful advice outside of raid.
The DC also works with the RO to keep them up to date with the performance of raiders and also how the raider is fitting in with the team in general.
During raid the DC is charged with insuring that DPS raiders have the proper gear and consumables and should keep an eye on pre-potting and know when the best time to use Lust and second pots are. If the fight calls for DPS to be split either physically or on special targets the DC is the one that insures this happens and that raiders know where they should be and what they should be targeting before it happens. If the fight includes adds the DC should know what the target priority is and insure that the damage dealers understand what and when they are supposed to be killing something.
The Healing Captain has much the same job as the DC but with the healers instead. The DC should know the capabilities of not only the character but also the player. The HC determines when big cool downs should be used and when other spot abilities could be helpful. They should also know how to direct healing during a pull to insure that if raiders must die the expendable die first. A good HC should be able to determine if they are over or under healing a fight and request changes be made accordingly.
A Raid Leader is simply the person who has been charged with executing the nights raid plan as set by the RO. The RL is charged with getting invites to raid sent out and checking players for gems, enchants, and consumables. Once the troops are assembled the RL sets the pace for the night, determines time in between pulls, when and how long breaks are, and how loot will be handled. Aside from pacing issues the RL should be able to get a sense of why a wipe occurred and what can be done to fix the issue. Keeping up with tanks and the role captains helps this immensely.
A raid leader also needs to be ready, willing, and able to sit players and fill empty slots throughout the night.
While there are a multitude of other micro tasks that could be delegated out this is a good start to understanding the various little things that go into not only raiding but just running a guild in general.