I decided to try something with my mule alt yesterday. With no exp in any crafting I ran him through all the certifications except alchemy as it is broken at the moment. Then had him do one actual writ. All the quests gave me a harvest area close to the city so minimal travel. I did have to search around a little for Jute to finish the actual writ. The result is nearly two levels of experience gained (I avoided combat as much as possible give the exp gain as 1%. Then exploration gave another 1%) and most of the crafting skills are close if not past level 2. I think it will be very good thing for new players or someone creating a new alt, although the quest verbiage needs tweaked as it sometimes sounds like only one path was an option.
The reality of the population though is that without changes this system is not going to be used.