Why I disagree with Co-Operation
Cooperation is the thing GW2 does correct. The issues you describe have roots in other parts of the system (i.e. lack of truly rare or soulbound mats dropped by random spawning un-farmable mobs).
The worst thing i think is allowing everyone to max all crafting so there will never be a real need for someone with specific craft or a true market for it.
ALso as Zerospin said, there are no rare drops or recipe(would love to see a instruction that can only be crafted only by people who acquire it)