(replace XYZ with any item you are waiting for)
Sereral MC or BWL runs moan about drop rates of certain items. Many classes wait for their T2 legs to drop at Ragnaros or the Priests for their epic quests, or the hunters for theirs. It depends on raid and is totally different for each which items or set items they are waiting for.
Common in these raids are the fixed raidleaders and loot masters, ie. they are usually the same person.
I will leave theory behind this on the side because it would be too technical and boring, but fact is that changing the raidleader and lootmaster BEFORE ANYONE enters the instance will change the loot composition. It has been tested and proven by some guilds. You can't predict loot this way, thats not possible, but you can increase the random factor.
So if you are in one of those raids where certain items never drop simply do this:
Load the person you want to be the loot list initiator (lets call him LLi) first, give him lead and he should give himself the loot master. Give the raidleader an (a) to allow him loading the rest of the raid.
Stay with the loot master until the first boss kill. After that he can give back the lead and loot master to the real raidleader.
Change this person as often as possible. Remember which person seems to drop the best loots and retest. Let him be that LLi for three runs and see if thats consistent.
You don't believe this? Let me give you some examples.
We only have seen the hunter epic quest item (the leaf) in Major Domus chest for a long time. Priests were pretty demoralized by this. So we changed the LLi and the priest epic quest got back to its normal 50/50 chance and all our priests now got their nice epic staff now.
The hunters never ever saw their T1 helmet drop, only ONCE in over 20 MC runs. We changed to another LLi and we got lucky: he pulled out the hunter T1 helmet from Garr. Everytime this one person is the LLi we get a high chance for hunter items (and some other classes, but the rareness of the hunter items was obvious).
We have one mage as LLi. Everytime he is raidlead and loot master we get a much higher percentage on random T1 drops than any run before. We usually found none, one or two. When he is the LLi we find 5-8 on every run. Our guild bank is pretty rich now because it allows us to sell those excess items as most classes now got their non bound T1 items full.
Before you dish this article as "can't be true" please try it yourself. As I said its IMPORTANT that the LLi is loaded first and enters, if possible, the instance first. If you are interested in details why this is happening let me know and I can post an article about the theory behind this.