I disagree with the declaration of open faced sandwiches not being a sandwich. You're telling me smørrebrød isn't a sandwich? I realize it's not American, but it's a sandwich, baby.
How could that be a sandwich?! I don't want to cite the dictionary but a sandwich is distinctly a food where fillings are sandwiched by bread. A smørrebrød or tartine can be tasty, but don't claim they're a sammie.
Curious, was the word "sandwich" used in that context before the invention of the sandwich by the Earl of Sandwich?
If not, I don't think you can use a secondary definition of a word as an example for the primary definition when the secondary definition exists solely because of the primary definition.
There was a logical flaw there perhaps, but I stand by my point.
Per a Guardian article linked side-thread, the sandwich was invented by our good Earl for a easily portable and hand-eatable food. One would not call an open-faced nightmare that.
It's like the Anglosaxon world starts with what we in Sweden would call a double sandwich (since it has two layers of bread) and declare that as the simplest form, thus considering our normal sandwiches to be "open".
Of course, in Swedish the word for an open face sandwich is simply "smörgås", which doesn't translate but does not at all have the layering (sandwiching) connotations. It means basically "buttered bread" ("smör" is literally "butter") although it's an old word.
In Germany we call it Butterbrot (same meaning as smörgåsbröd/smørrebrød) and it's still far more popular than the sandwich (though most commercially available bread dishes definitely are sandwiches).
There's an urban legend (referenced in the Etymology section of the English Wikipedia article) that the sandwich was created by the Earl of Sandwich (or his servant) because he liked to eat buttered bread while playing card games and found it easier to eat if he added an extra slice of bread on top.
If you tell a German to make you a sandwich, you'll most likely get something resembling an actual sandwich. Though it'll likely just be buttered bread with an extra slice of bread on top and just one type of cold cuts or cheese -- because we're just not used to making actual (multi-layer or stuffed) sandwiches.
By that logic one could take any dish in the world, slap a slice of bread in there somewhere, and declare you have a sandwich. Which many may consider an insult to both sandwiches and all dishes that are not sandwiches.
It's absolutely not a sandwich. "Open-faced sandwich" is a travesty of a name for a lone slice of bread with something on top. We should call it what it is. A disappointment.