I did end my statement with the possibility I was a crazy old man.
My real reasoning was that if your favorite aircraft's flight model was changed, that it might throw off your aim for a while, maybe until you got used to it at least. Could happen. Changing the convergence might be something I happened to do at the same time I automatically adjusted to something else, a coincidence.
I always was a fan of really close convergence and shot taking, but that can have it's disadvantages. If you get used to always taking shots while very close to your opponent, you run the risk of collisions and also of having your aircraft damaged or destroyed if their aircraft explodes in a spectacular fashion.
In light of this for some time I have been trying to remember to take shots earlier which not only gives more time to make them but gives the possibility of landing more hits. For years I had my convergence at 150m, but I thought it would be fun to try and stretch it out by 50 or 100 meters.
190A shotmaking:
http://www.youtube.com/profile?user=.../0/AqIvrh7tdQY