All,
Absolutely correct on this one, very effective method and the basis of the tutorial in my sig! From what I can gather from reading German SOPs, I think these procedures closely reflect historical doctrine. Included in my tutorial is also an historical method of determining target speed by timing bearing change also referenced in German period documents. Please check it out and let me know your thoughts!
http://www.subsim.com/radioroom/showthread.php?t=229792