From the Bitcoin wiki page on transaction fees:

Transaction priority is calculated as a value-weighted sum of input age, divided by transaction size in bytes: priority = sum(input_value_in_base_units * input_age)/size_in_bytes

If I read that correctly, that is directly proportional to BTCDD, so whatever effect concerns you has already been built into the code.

On Fri, Sep 11, 2015 at 3:21 PM, Vincent Truong <vincent.truong@procabiak.com> wrote:

Would this alter the way txns will be prioritised in order to try to win? You would always pick txns with the best BTCDD to maximize your chances of being the block to build on.

I see this as potentially being a bad outcome for bitcoin's fungibility.