Finally got time to play with the tandem feature on Version 11. I used a frame I built about 18 months ago as the test.
At that time I had to model the front on BikeCAD, export that image and underlay it beneath the model of the rear. This involved a good deal of tinkering to make the front "chainstays" the stretcher tube and rear "head tube" overlay the front seat tube.
With V11 it's a two minute job. More great work Brent.
The frame itself needed a low rear standover and yet still be stiff enough for loaded touring. The oval rear toptube runs continuously to the downtube and is pierced by the front seat tube and the diagonal brace tube.
Unfortunately the only picture I took is of the uncompleted frame in the vice (I've flipped it to match the BikeCAD model)