I don't think that's a valid argument. Fast shifting does not have to mean poor throttle control, or in this case intentional torque overlap to create the illusion of a "sporty" shift.Well it is sport mode!
Case in point - take what's considered to be the best dual clutch transmission out there, Porsches PDK. In its most aggressive settings it does not do any torque overlap because, well, that's actually bad for performance driving because it can upset the chassis and lead to traction loss mid corner. In Sport plus on a PDK, you get a faster shift, but it's still just as seamless as the more comfort oriented settings. Only the time to take the shift changes, but there is not torque overlap added.
On the other end of the scale is BMWs ridiculously exaggerated torque overlap on its M cars in sport plus (I used to own an F80 M3 and this was my biggest complaint about it on the track). They do it because street drivers who will likely never see a track think it's sporty and exciting. It literally holds both odd and even clutches at the same time for tens to hundreds of milliseconds which results in a chassis-upsetting "smack" in the butt dyno during WOT upshifts. It's silly boy-racer stuff that doesn't belong in a real performance car.