Doesn't work.
must have just been luckon brandons part.
two different accounts both lvl 20's tried. about 5 runs for each and this yielded no dyes (only one purple out of the collected 10 runs from both).
even if these guys DID drop runes, they take forever to kill if you are a warrior because they not only heal themselves but their little buddies heal them as well (making it hard to interupt their healing spells and the such).
i can imagine if this DID work that an elementalist would be able to 'turn them' all into dye very quickly
theres much easier places to find dye anyway..