Any references to the work on using slime to mimic the UK rail network that you mentioned? The best I could find was the following from http://www.springerlink.com/content/7tw4745823645128/
"In practical terms such a process may also be witnessed in the evolution of real infrastructure networks, such as British railways following the Beeching reviews in the early '60s [8,9]. In these reviews, the flux along various routes was measured and routes with too low a level of traffic, mainly branch lines, were targeted for closure. At the same time, major routes were strengthened to cope with the expected source-sink relationships for both passenger and freight traffic. Interestingly, the reports focussed on efficient rather than any explicit consideration of resilience, which may explain the sensitivity of the current UK rail network to disruption."
Where: [8] British Railways Board: The development of the major railway trunk routes (1965) [9] British Transport Commission: The reshaping of british railways - part 1: report (1963)