I don't know whether the staff at Unlimited IT were aware of RFC 2549 or the old (in computing terms, anyway) adage "Never underestimate the bandwidth of a station wagon full of quarter-inch tapes." but it seems rather likely.
For bulk data transfer, where interactive response isn't needed, shipping the files on some sort of storage is generally going to be faster than the network. A carrier pigeon carrying a 4GB USB drive could come in level with a fast 4Mbit/s connection over that sort of distance, and any connection slow enough to complain about is going to get defeated easily by the pigeon.
The UK academic network, and its European and US counterparts, is in the GBit/s range, at which point the carrier pigeon starts to look obsolete, though a vehicle full of DVDs does not. It's unlikely that there'll ever be a time when the quality of network available to the general public will beat (over the short and medium distance, anyway) a carrier pigeon with the compact storage device of the day, now that the storage devices are small enough for a pigeon to carry at all.
