Hi Exupery,
Thanks for the detailed explanation of the swan's neck function!
I know that it matters not whether if the watch has a second's function or not, the point of the regulator is to make the watch more accurate when finely-tuned.
It's just that when I see the PAM 21 (which indeed is a Grail to me), it somehow intrigues me why did Panerai not have a swan's neck installed back then (maybe for historical reasons)?
Since the swan's neck was used widely way before 1930's, it surprises me even more that the original 3646 and 6512 also did not have the movements fitted with it. I dont know, maybe it's me but wouldn't you think by keeping more precise time is crucial to the frogmen who have to go on bombing missions with these timepieces?
Just curious, thats all...