We hire... not necessarily Dessa. Anyone, for example a Barbarian (with one goblin) without logistics. They should run at the same speed, right? Right. But here it turns out differently... Anyway, see for yourself.
A save of a map where Crag Hack and Bogarus are starting in two cities, each with one goblin. Now try to move both downwards. In the end, we have Crag who moved one cell further....
And overall, it was easy to check on the Conflux... Lacus and Calt always have water elementals with them. Try placing two Confluxes parallel to each other, with Calt (Lacus) in one and Aenain, Pasis, Grindan or similar in the other, and try running them parallel. ;)