Hey Marco, you devoted so much of your time for giving all this so detailed explanation! This was very very helpful! Thank you heartily my friend! : - )

Now as to 'zebra' analysis in Rhino... is there, really, a way of avoiding such surface continuity defects when working with so many filleted edges on a model? What may be the 'key' element, in modeling process, for avoiding such continuity problems in surface flows? Any related hint?