There is a new TH thread on Blue Garter (
http://www.bluegartrls.com/forum/showthread.php?t=63785) where people are compiling data on several mobs. Here are some charts based on the TH0, TH1 and TH2 data on dhamels.
Data:
Drop Kill is the total number of drops over the total number of kills. It is a measure of loot output and can be greater than 100% if you get more total drops than the total mobs killed.
Drop Mob is the chance that a mob will drop anything. It does not take into account what drops or the number of drops.
Drop Groupings:
Drop Stats:
Analysis:
These charts are based on 1000 kills for each level of Treasure Hunter. On a basic level you can see that TH increases the chance that something will drop from a mob (ie the chance that 0 items drops decreases). It also increases the chance that multiple items will drop (2-drop 3-Drop and 4-Drop). Getting 3 and 4 drops is still rare even for Dhamels but TH does increase it.
The distance between Drop Mob and Drop Kill on the second chart is the effect of multiple drops on your loot output. If every mob dropped 1 item, the lines would be identical.
The combination of those two effects, increases the loot output from 24.9% (TH0) to 56.1% (TH1) to 79.7% (TH2). How TH affects each drop, or combination of drops is more complex and we need more analysis.