I doubt he would prefer to do that, and carrying two rapiers would be silly. Lady Teldra as main gauche is much more practical. She won't be having dinner with bandits or random sneering Jhereg as the main course. Perhaps just as important, Vlad's not exactly going to be swordfighting with her. It's sort of like bringing a tank to a knife fight. He's an *assassin* rather than a front-line type. Lady Teldra will probably be attacking in stealth more often than not, and seems well suited for that. On the other hand, there will be times when he wants to show a little blade - and the only people who will stick around once they feel the power of that blade will be those knowledgeable enough to fear her.