Hmm - I'm thinking maybe my gun tweak files are screwed up or something (though they seem to work for some other parameters). First, I tried setting the elevation speed to .5 as suggested above, and in game my gun elevated just fine but basically refused to traverse
So, I tried again, this time putting the elevation speed back to stock value and setting the traverse speed to .5 (in case they were just switched somehow), but I couldn't notice any difference in game - the gun traversed and elevated just as normal and I couldn't detect any loss of stabilization at 7m/s wind speed (highest wind I ever try using the gun in anyway, although since the US boats seem to have a higher freeboard than the German ones I suppose I might try using it at up to maybe 8m/s or so, at least for the stern-mounted guns).
Guess I'll try the D/L'ed file tomorrow and see if I can tell the difference.