Improved dodge is useless for shamans, don't waste your time on it.
When the Omens augs came out, I was lucky enough to get some slugworms and decided to try my hand at making an aug - I ended up with a 6 STR, Improved Dodge II aug and was "dead chuffed", so to speak.
However, after spending hours in Nadox testing it, I couldn't see any increase whatsoever in dodges, other than random variation within the RNG.
With a dodge skill of 80, you'll dodge around 2% of the time (from various parsing I've done up to SolRo level mobs). With my ID2 aug in theory it would have boosted my dodges from 2% to 2.4%, but in practice it was entirely lost in the fog of the RNG. I ended up destroying the aug and replacing it with a much more useful 55 HP aug - yes, I may have ended up dodging a killing blow, but the chance of that was so slim that I preferred the constant boost from an HP aug.
(Edit: and 70% of my time in EQ is spent soloing by tanking mobs "in the face" - yet even with that I feel ID is a complete waste. I'm a fiend for +avoidance gear though!

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