On the other hand some foreigners had a better time with questions-- Robert Nadeau and Henry Kono had some better luck. I think there may have been 2 things going on: 1) Cultural convention, where students don't ask questions of the teacher, and instead just copy and try to figure it out, and 2) O-sensei didn't want to spoon-feed the answers away. I think O-sensei was just iconoclastic enough to care less about #1 than #2; but the Japanese deshi may have taken #1 for granted as well.
Certainly, some of the foreigners weren't quite as shy about asking questions.
Of course, whether or not they had the background to decipher the answers is another question. Robert Nadeau, for example, didn't even speak enough Japanese to ask those questions directly - I'm not criticizing him, but you have to place things in the proper context.