Searched the forums and wiki, didn't see anything on this. So does this work here? Or did it on AK/Live? I never played a ranger back in the day, so this is new to me. Does it stack with worn haste, or in my case, Swiftwind. Plenty of peeps saying so here on alla going back to 2001. http://everquest.allakhazam.com/db/item.html?item=6186
Haste on quiver should indeed stack with worn haste, spell haste and I think bard overhaste. Fleeting quiver totally worth getting. But at the same time we really aren't doing bow DPS yet much, most days and raids I don't even wear a bow.
All that said I have no idea if it's working accurately here. I have fleeting quiver but have not parsed or shot enough to notice.
Devs have never actually answered this when asked and no ranger has ever parsed it because we're lazy. Quiver haste should be 1/3 of weight reduction amount and should stack with worn item haste. So 20% bonus for using a Fleeting quiver. Without this mechanic, quivers, especially the work needed for Fleeting, would be completely useless.
Quiver haste is implemented here, and is applied after other haste bonuses should it'll stack. Now whether it works or not I don't know but I don't see anything noticably wrong with the code.
I just did a quick test in game, and I got 2 extra arrow shots per 10 seconds of sustained archery with the fleeting quiver on, so its haste boost is working.