Strength vs. Agility in dealing damage:
In bear form:
Strength (str) adds attack power (AP); agility (agi) doesn't. When tanking with a group, though, the extra armor and dodge the agi gives may be more important than dealing some extra damage, unless that bit of damage would maintain aggro that would otherwise be lost. The extra agi also yields more critical hits. The direct damage effect of crits is discussed below, under cat, but these also result in slightly more Rage generation with the Primal Fury talent.
In cat form:
1 str yields 2 AP. With 5 points in the Heart of the Wild talent, cat-form str is increased by 20%, so an item with nominal str n effectively adds 2.4n AP.
1 agi yields 1 AP.
As always, agi also increases crit rate.
(Now for the important, usually missed part.)
There is no constant, linear exchange between AP and crit rate. The higher your AP, the greater the marginal utility of a bit of extra crit rate and lower the marginal utility of a bit of extra AP. And vice versa. Damage rate = AP * (1 + crit rate)
Ex:
Start with 100 AP and 20% crit rate. Damage rate = 120c (where c is some constant converting attack power to damage; we don't need to know what it is to make these comparisons)
Add a piece of equipment with some agi that results in 105 AP and 21% crit rate. Damage rate = 127.05c
OR add a piece of equipment with some str that results in 110 AP and 20% crit rate. Damage rate = 132c.
The str helps more.
Now start with 1000 AP and 20% crit rate. Damage rate = 1200c
Add that agi gain for 1005 AP and 21% crit rate. Damage rate = 1216.05c
Add that str gain for 1010 AP and 20% crit rate. Damage rate = 1212c.
The agi helps more.
That's non-combo damage. Also remember that, with Primal Fury, crits add extra combo points, so that even a slightly lower base damage rate with more crits might be better, but the precise measurement of this is more complex and omitted here. In many cases, the damage from the agi will be higher even before worrying about that.
So, for a given set of equipment or enchantment alternatives, look at the effects on your AP and crit rate to determine the base damage rate effect, and then consider also the value of the armor and dodge gains. Considering only damage dealt, whether a given amount of str or agi is more valuable depends on what the rest of your equipment is.
(The vast majority of the time with my feral druid, equipment with agility bonuses has been the most valuable overall, sometimes outweighing superficially much larger total numbers on alternative pieces.)
Edited, Apr 24th 2007 2:53pm by GoedelOnNathrezim