ReplaceAll behavior not completely correct

[corywalker]

//&TestComment{"Notice how rules are applies until no further rules apply. If we only used ReplaceAll, only the first step of simplification would occur:"},

// Expreduce does not currently return the following: //&SameTest{"Log[a^b] + Log[b^(c^d)]", "Log[a^b*b^(c^d)] /. logRules"},

[rljacobson]

Note that ReplaceAll is the only known general purpose function that traverses the expression tree in preorder.