No the "Edge line" on the top is like "lines seams generator" in nurbs ;)
It's only Edge Style drawing!

For the rapidity I believe that I can made all this forms in less than 30 seconds ;)
But only because it's a very simple symmetric form !

If you don't want use the extra plug mirror : you must make a Copy Move + the Scale "-1" (shown and explained above)
so maybe 5 seconds more !

But use plugs is a normal way in sketchup ;)