I made a suggestion about queuing talent actions previously but maybe this is a bug/issue?
Ranger 25, with crossbow or bow auto-attack (2.5 attacks per sec or .4 sec cooldown | 1.25 attacks per sec or .8 sec cooldown) First 4 action keys:
1. Ranged attack
2. Black Fang (3 sec cooldown)
3. Detonate (9 sec cooldown)
4. Blood Fang (12 sec cooldown)
Obvious damage cycle. I activate 1. range attack for initial shot/debuff then cycle through 2,3,4. After the first cycle with the cooldown timers are all running I expect to run through 2,2,3,2,4 with ranged attack shots firing in between.
With auto-attack on, no matter how fast I am there's always one ranged attack cooldown right after the cooldown finishes on 2-4. I have to wait for the first ranged attack to complete before I can activate 2-4. So say for example Black Fang:
Black Fang (3 sec) + Ranged attack (.4 sec) + Ranged attack w/ Black Fang activated (.4 sec) + Black Fang (3 sec) ... etc...
Basically Black Fang fires 3.8 seconds after the first use and I really have to pay attention to it because the cooldowns become misleading and I can't just hold the key down or queue it until it fires. If I use Quick Draw, then Black Fang has a 1.5 sec cooldown, but lags .8 sec.
Note that this lag does NOT occur with auto-attack off. What does happen is my ranged attacks have a ~.2+ second delay handling rapid keypresses. I'll get more DPS out of Black Fang, but less out of my normal ranged attack without auto-attack.
Hopefully that made sense. It's fairly easy to see. auto-attack on. Try and get BF to fire right when the cooldown is over. Doesn't seem possible =/