I realize that I might be preaching to the choir here, I've had enough bad experiences with Wandering Palaces "Speed Runs" that I wanted to open up an honest conversation regarding the practice.
Wandering Palace Speed Runs are the, current, preferred method of farming Philosophy and Mythology. Done properly they are extremely fast and efficient. However, they are also extremely stressful and very easy to mess up. With that being said, here are my thoughts and tips regarding them from a tank point of view (Paladin is my "main" job). Please note that I'm going to try and avoid so called "bright lines" (i.e. you must have exactly 3,912 hitpoints as a bard or more otherwise the run will fail) and speak more in generalities.
1. Communication: While there is a standard format for speed runs there are also a number of places where things can differ slightly. Whenever I join a /shout speed run, I do so with the expectation that the group will stick around for a few runs. As such I like to let the group know on the first run what my pulls look like and what I expect from other group members. For example, my second pull is the second half of the mobs leading up to the first boss. The only one that needs to die is the final Tonberry if everything is slept prior to pulling the boss. However, I've had plenty of times where half the group expected us to sleep the pull and the other half expected us to kill it all. Needless to say that in those instances, wipes have ensued. Communication helps prevent this misunderstanding.
2. Wipes will happen and there will be waiting around. As mentioned, speed runs are very stressful on tanks (and healers I'm sure). A single slip up will result in a wipe. If you're going to ragequit for every little wipe, you may be better sticking with your FC who will put up with your attitude. Also, there are times when I will be waiting around. It takes a certain amount of MP to pull everything and hold aggro on it. If I lack that MP, I'm going to wait a few seconds before pulling the next pack. Also, in the "maze" area there is one big Tonberry that is particularly annoying. After opening the door and going up the stairs, there is one that paths right through the middle room with 3 skeletons and the door device. Many times we'll need to wait for him to path by (especially if he's coming right down the middle of that room). Personally I take this as a good thing because it means that we're making good time.
3. Gear does matter. I'm not going to list bright lines. The gear level requirement will differ from group to group but it does matter. The better the tank's gear, the longer s/he can stay alive. The better the healer's gear, the easier it is for him/her to keep the tank alive. The better the DPS gear, the faster the stuff dies. So you saw a youtube video where a group wore swimsuits and completed the run in less than 10 minutes? I don't particularly care. If such a group exists they, likely, have been playing together for awhile and have good synergy with each other. Your typical /shout group isn't likely to duplicate the feat without a lot of practice.
Anyway, those are some of my thoughts on them. Personally, with a good group I really enjoy them and consider anything under 20 minutes a "success" with my best runs around 14 minutes. But I've also found them to be the most frustrating thing possible when grouping with people who have overinflated egos. As I mentioned, I usually play a Paladin as my "main" job and part of the problem with that is I don't get to see how other tanks actually do the instance. I had to learn on the go.