I have made a 3D bow tie quilt and didn't have problems sewing things together but I did mine differently that the tutorial listed above. Sorry but I don't have a picture to share.
Here is the method I used. There is hand sewing involved but that is what I liked about it. It was a project I could start away from the machine and then when my blocks were done I assembled the quilt top on the machine.
http://mylifeisastitch.<wbr>blogspot.com/2011/12/fabric-<wbr>folding-one-bow-tie-obsessed.<wbr>html
I know this doesn't help with the question asked but for those of you who might like to make a 3D bow tie quilt this is another option that doesn't have seam issues.
