It was the bottleneck on the new Research tradeskill. They lifted the cap to 300, but all recipes beyond 227 trivial require some amount of it.
Since most post 200 tradeskills require 20+ combines per point (and it gets worse near 300), you would need many 1000s of these to get there.
On most servers, vendor diving these was almost impossible. We were managing as a guild to pull in say 5 a day.. so.. in year you might farm enough.
This would be like saying all of the 200+ trivial recipes of tailoring required Silk.. and that silk could drop from any mob in the game, about once every few hours. No specific mob to hunt, just kill them all and you will get one.. now and then.
Look for new Expert Researchers within the week (I know of at least one that was in the Beta and smart enough to stockpile Cyrstallized Sulfur *before* DoDH rolled out).. Masters soon.