To capture base A, you first had to capture base B. Base A could then be used to capture Bases C, D and E, with the number of capturable bases varying. The base capture paths were permanently fixed, so it was the same for every country.
This means if Nits were pushing into Bish Land and captured a V base at the end of a one-way link, then to recapture that base the Bish had to follow the EXACT same line of capture even if they had an airfield 5 miles away.
While a novel idea, it wasn't very well-executed and heavily flawed. CVs were almost useless since they had no effect on the base capture order.
What would have worked better was that ALL adjacent bases would be capturable, to eliminate the unintuitive one-way captures.