Originally Posted by TandemGeek
I suspect it's a combination of things, and perception is just that... perception. The Burley should not feel "objectionable" by any stretch; however, if a Co-Motion became the benchmark for a subsequent ride the bikes would definitely feel different.
Again, too many variables to address (i.e., tire size, psi, shockpost vs no shockpost) which is why test riding is so important... if only to vanquish the demons of preconceived notions or to satisfy subtle biases that may have crept in during early research that skew perceptions.
A shockpost set too loose will definitely throw off a newbie team (as I experienced first hand) as every steering input causes the stoker's weight to move in the opposite direction, giving the sensation that there is some sort of hinge located mid-frame.