Nobody mentions the cross straps needing to be either side of the butty stem, this seems to allow much more control of the butty.
If the straps bring the butty up to the fender when crossed over the stem when they are uncrossed there is more room for the butty to move around. When crossed the butty is remarkably well behaved without a steerer and tracks almost exactly the motor, very neat. Ideal for entering single locks having the starps tight as it controls the butty, keeps it from hitting the throat or tail of the lock.
I'm very new to all this butty business but trying to learn as much as I can. Very interested to hear anyhting to do with handling pairs.