|Darksol the Painbringer|
I'd say since you forgo the dodge bonuses, you never have these dodge bonuses. So, they never get to stack. You can't stack things that aren't there.
If that's the case, then the feat doesn't even function because you're suggesting that there is no Dodge Bonus for the DR to be converted from, which means you have DR 0/-. I'd rather go with the interpretation that the feat actually does something, instead of creating some weird interpretation that leads to the feat being equivalent to Monkey Lunge or pre-errata Prone Shooter.
Even if it did work that way, you're still resulting in not gaining an equivalent amount of DR in comparison to the Dodge Bonus you gain from the two activities.
Re-reading the text, it actually sounds like you only forgo one Dodge Bonus set, and not both, so the idea that having a +2 Dodge Bonus to AC and DR 3/- (or vice-versa) is a lot more likely than simply losing all Dodge Bonuses gained from the activities for a mathematically sub-par benefit (and no, I'm not referring to DR being inferior to AC).