I believe that Burly used thick walled tubing so with a lot of tubing used on a tandem it is heavy. Not all steel tandems are built with that tubing and as a result they ride much differently. I have a steel tandem that has tube walls only 57% as thick as what I think the that Burly has. That is almost a 57% lighter frame in the same size. The wall thickness also effects the feel of the frame.

Still the Burly is a workhorse and you should not have to worry about dents in the top tube.