Simple zig-zaging is easy to counter. The speed drops by a few knots and you can decide when to shoot just as the ship starts a turn into you (going for 90 AOB). But that's not what Tater's diagram is about.
You can see there that the entire convoy switches direction by 20 degrees at irregular intervals every 5-10 miles (i don't think it's minutes). That would make shadowing a convoy extremely difficult, the general course of the convoy would need a very long time to "decrypt" and positioning for a perfect 90 shot would be almost impossible. You'd need to rely more on visual observation and less on plotting. For me such a difficulty option would have the same impact on gameplay as "wolfpacks" would. And I believe it's very easy to implement.
What do you think Lucian? By the way your name is very familiar to me. Did you study at the Automatics Univeristy here in Bucharest?