The 28-520 caliber base has been modified and reduced from 5.2mm to 4.7mm. The World Time module is 3mm.
The 5930 is 12.86mm whereas the 5980 (chronograph only with simple date) is 12.6mm and the 5960 (with AC instead of WT) was 12mm (thickness taken in the middle but 13.55mm if you take into account the lugs' end going deeper a little) so this is a significant evolution improvement.
Furthermore, the construction has completely integrated the dial in order to be used as a kind of bridge by itself (as you can see in the video I posted in my 5930's recent review).
Great work from Patek's watchmakers and this is something I like a lot.
Thanks for your comment Russ.
Cheers, Mark
This message has been edited by Mark in Paris on 2016-04-21 07:36:45