I am restoring an old Monogram 1/32 Wirbelwind, and am truly admiring the work of Sheperd Paine: a beautiful rendition indeed. The only thing is, he has track segments affixed to the turret, and whilst it looks damned good--I have yet to find one picture on the internet of the real thing, with tracks affixed to the turret! Seems to me, that one would not want to slow the traverse of the turret down by any degree whatsoever. Well?

No track links on the turret in any of the images in the Nuts and Bolts book

The armour was so thin on the turret that a hit from a tank projectile would probably send the track links into the interior

You're absolutely correct about the added weight slowing down the traverse. Indeed, I knew a Churchill tanker whose unit fought in Italy. They experimented with affixing track to their turrets for added protection. They found that the slight slowing of the traverse was not acceptable given that a tank that fired first was more likely to win a tank-on-tank encounter. This info was disseminated to all Churchill units in the MTO. Later, he saw photos of the practice going on with Churchills in NW Europe and was befuddled that those units didn't adhere to the same thinking.

Since traverse is manual and tracking an aerial target is rather time critical, I'd be very doubtful that this is other than artistic licence. Why make life harder for yourself with the principal role of the vehicle in exchange for a minimal increase in protection? There was a reason for the thin armour on the turret (arguably more a shield than a turret anyway) and it was never expected to protect against anti-armour weapons.

Well, it does indeed look like there is not a single incidence of track segments hung or welded onto the turret of the Wirbelwind or Ostwind for that matter, and for good reason. It does look great the way Shep did it though.