War games held by "Generalmajor" (Major-General) Kurt von Tippelskirch, the chief of army intelligence and Oberst Ulrich Liss of "Fremde Heere West" (FHW, Foreign Armies West), tested the concept of an offensive through the Ardennes. Liss thought that swift reactions could not be expected from the "systematic French or the ponderous English" and used French and British methods, which made no provision for surprise and reacted slowly, when one was sprung. The results of the war games persuaded Halder that the Ardennes scheme could work, even though he and many other commanders still expected it to fail. May wrote that without the reassurance of intelligence analysis and the results of the war games, the possibility of Germany adopting the last version of "Fall Gelb" would have been remote. The French Dyle-Breda variant of the Allied deployment plan, was based on an accurate prediction of the German intentions, until the delays caused by the winter weather and shock of the Mechelen Incident led to the radical revision of "Fall Gelb". The French sought to assure the British that they would act to prevent the "Luftwaffe" using bases in the Netherlands and the Meuse valley and to encourage the Belgian and Dutch governments. The politico-strategic aspects of the plan ossified French thinking and the Phoney War led to demands for Allied offensives in Scandinavia or the Balkans and the plan to start a war with the USSR. Changes to the Dyle-Breda variant might lead to forces being taken from the Western Front.