Agreed Paul, on the F-15 project while doing the directional study we tried the center line location and it was really bad over the flight range we needed. You could get the needed stability but it looked like a third wing panel. The verticals we ended up with are much bigger than those originally proposed.

It could be North American had the same problem. That twins they ended up with still violated the storage height so if you had to do it just fold one big one. I guess a weight tradeoff would select the winner of that configuration and apparently the single vertical won. Interesting stuff indeed.

That basic twin everything configuration you mentioned is hard to beat. We once tried a low wing, variable sweep, 2 engine, configuration but it still retained the design elements you mentioned.