Thanks for the link, Flying Free, and I understand the connection to Clichy much better now. I answered the question in the context in Craig's piece, 1950'-60's, but I think your question goes further back. There was a very good description in the Clichy link of how to produce filigrana and zanfirico rods, two very Murano techniques. The Murano connection seems to be acknowledged in the text.
In another related thread on this topic, someone mentioned that Venetian Glass was produced by Jenkinson's of Norton Park in Edinburgh, the company that would become Edinburgh and Leith Crystal. I have a piece of that passed down from a relative. The piece was most likely created by the Venetian glassblowers that Jenkinson's imported to Scotland. (It must have been the climate and the food that attracted them. ) So that even when very Murano techniques are used, the glass may not come from Murano, which I think is your point.
I've found the same as you the short time I've been collecting. When I started collecting, I saw all glass in very discrete, separate categories. But the more glass I saw and handled, the more I read about glass and how it was made, the more I saw connections, influences, and homages in every piece. I remember being in the museum in Murano and seeing ancient glass for the first time and thinking how modern they looked. It was the same with seeing Marinot pieces from before WWII in France and seeing how Scandinavian they looked. I've become better at saying what a piece is likely to be, but no more than that. I think I can identify many complete impostors, but I'm not going to reach the level of someone like Ivo who can make the fine distinctions between similar pieces of glass.
One of the funny things I've noticed, though, is that the better I've become at id'ing a piece, the less I care about where it comes from, at least for the pieces I really like.
David