Thanks all for all the replies, especially the photos.
We're iced in at the start of the Coventry at Fradley Junction at the moment (so narrow canal with limited scope for mooring abreast let alone towing abreast). We'll be heading up the T&M next - after Woodend lock there's a good few miles of lockless canal. Will wait for the thaw and just man up and have a go I think.
There's 5 of us living across the 2 boats - 3 of which are children (2 1/2 yo twins and a 14 yo). It's, stereotypically, usually me who moves the boats while my wife watches the little ones. The 14 yo is happy, and more than capable, of sailing either boat but not confident of doing so single handed - once he is happier doing so it'll solve all the problems.
We're never in any rush to move far in a day and I really don't mind the walk and doing 2 trips each time - towing would just increase the distance we could do in a day.
Thanks again for all the replies - will make sure I post (hopefully successful!) photos when I try it.
Matt.