In theory, yes. But not really, for a few reasons:
1. Parry and dodge do not work the same. Dodge works on all attacks, parry works only on those in front of you. Also, while dodge does nothing to your attack time, parry decreases the time until your next attack, based on
this formula. You can also see that for warriors, parry increases your rage, while dodge does not.
2. Certain abilities that are available on a dodge or parry work different. Mongoose bite procs on dodge, counterattack on parry. Also, when you dodge, warriors can use overpower.
In terms of damage mitigation, yes 40+40 is equal to 80% of one, but there are subtle differences.