E3 spark plugs....Gimick or?

The problem with having three gaps in parallel is that only one will break down on each firing. (The voltage across an arc is very much lower than the peak required to create that arc). Once one of them fires, the other two are just along for the ride. You could argue that they actually get in the way of the flame kernel formation...
The only advantage I could think of (other than snake oil advertising) is that there are three points instead of one, so the normal wear should be tripled.