The Wormser flask with the large top pictured in my first post, is not a real extreme example of this variant. I have seen a number that are much more pronounced. The test to determine if you have this "large top" variant is quite simple. It was devised a number of years ago at the Reno Bottle Show by my friend and flask collector Jon Lawson.
Simply turn the bottle upside down and stand it on it's top. RELEASE YOUR HAND!! The release time is the critical element in determining the "rating" assigned to your specimen. A top example might have a release time of .5 seconds or less!
If you are showing your bottle at a location with a cement floor, please add at least 2.5 seconds or an appropriate amount of additional time to the experiment.
Being in a modestly sober condition is also quite important.