I'll be interested to read your follow-up post on the differences between offering phone support in Japanese and English. A few of the interactions you described here sounded distinctly Japanese to me.
Could one of the folks down-voting this please explain? Did this come across as sarcastic, or offensive? I'm honestly curious, for example, whether most westerners would be as courteous, or whether the taboo against asking about proficiency would feel the same in both cases.