No apologies necessary, I have a fair share of those myself, lol.
I could be wrong, but I think DD is more about recapturing traditional man - woman roles, not unlike "50is idyl". DD couples rarely venture into BDSM other than an occasional spanking and in fact they often take offense at being labeled BDSM. TPE is about D/s regardless of dominants partners gender; for more about TPE look to posts above.